3 times ( 5 + 20 / 2 x 5 ) BECAREFUL! Many will do this WRONG!
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- čas přidán 15. 08. 2023
- How to use the order of operations - PEMDAS (parenthesis, exponents, multiplication, division, additions and subtraction).
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165.
Depending on the country, the name of the order of operation may differ, but the concept is the same. I learned BEDMAS... Brackets, Exponents, Division and Multiplication, Addition and Subtraction.
Yep. I learned BODMAS as well (of just meant exponent) :) Got 165 as well.
What's the point of a pnemonic (pedmas) to help you remember when all it does it make you do an error if you don't remember that it actually is pe(dm)(as). I would've expected more logic from math people who came up with this.
When I learned the order of operations, it was presented in a graphical form, with the various groupings on separate lines, with an arrow pointing down on the left, with the label, "Simplify," and an arrow on the right pointing up with the label, "Solve." That way it was clear that multiplication and division were in the same class of operations, and addition and subtraction were in a different class of operations from multiplication and division, but were in the same class as each other.
The teacher gave extra credit on tests if you drew the graphic on the upper right side of the test paper, and he would indeed occasionally have questions where you were asked to, "Solve," instead of, "Simplify," and to get the correct answer it was necessary to reverse the order of operations.
That was over 30 years ago, and I still remember every detail of that graphic, so it was entirely effective.
Yeah I solved this with bedmas as well 👐
@@mkovis8587*mnemonic
3(5 + 20 / 2 x 5) brackets first .. and 20/2 first
3(5 + 10 x 5) then 10 x 5
3(5 + 50) then 5 + 50
3(55) then 3 x 55
165
Totally agree.
I do agree as per PEMDAS rule.. but application in real world such as physics, chemistry, advance math, engineering does not follow this. juxtaposition is included in the rule. hence your answer is still wrong
Hello, I am British and we use BODMAS, eg Brackets, Of (to the power of), Division, Multiplication, Addition, Subtraction. Using this mnemonic means you don’t have to complicate the process further by having to remember to check on the order of the division and multiplication within the brackets. Division is always carried out first ie before multiplication.
No in Bodmas what you do is based on going left to right in the equation in this case divsion comes first in the equation (going from left to right) so you do division first but if the multiplication came first left to right then multiplication would come first.
@@FranklinThe1You’re right but they’re not wrong. Doing division first always gives the correct answer because it’s simply multiplication by the reciprocal of the number following the division symbol, and it doesn’t matter what order you multiply in. There’s no reason to go left to right. Just understand what division actually is and you’ll be fine. I hate the people just mindlessly repeat rules they’ve learned without understanding them.
Yes thats right we use BODMAS in UK and use the nifty expression Bugger Old Dad! Mums Arse Sags - so as to handily recall it when doing operations
Correction......."if we have both multiplication and division, neither has priority and we work from left to right". So the answer is 165.
I was also taught that multiplication had equal priority to division, but another respondent said that division comes before. I can’t agree with that as they are interconnected functions.
In my head
I have spent my life feeling stupid because I didn’t understand this stuff and now I realise that I just wasn’t taught the basics properly. I wish that I’d had a teacher like you, Sir! My life would have taken a completely different direction. This 62 year old thanks you very much!
Me too! Im 63
I'm from overseas and I noticed most teachers are the same THEY DON'T KNOW HOW TO EXPLAIN MATH & SAID IT YEARS AGO
Yes! this teacher was born to be teacher
Don't feel bad.
The dude F'd Up the grammar of the opening statement. So he's no genius 😂
@@tonyferreira6679
See, another english scholar.
I am a 77 year old woman who had a couple of very intimidating math teachers in middle school so I never mastered algebra and have
regretted it all these years. Thank you for your CZcams channel. I watch it every night on TV and I am determined with your help
to finally be able to conquer this and cross it off my bucket list. Thank you, John, for your patient teaching.
Nobody tell her that this isn’t algebra…
@@LivingroomTV-me9oz I am sorry, but algebra is imaginary. It does not exist. What is a number? It is a symbol indicating how many objects, thoughts, concepts, items exist in a given space. (...) is described as the number 3.
What is a letter? A letter is a symbol indicating a sound. "A" is a sound. "Three" is a word, a sound made up of letters, but "three" is NOT (...). Just as you cannot add a stone to a board or a piece of paper to a dog, you cannot add, subtract or do anything combining a (...) to a letter! It simply does not work. Yes, you COULD mulch the board and reduce the stone to sand and throw them together, but ultimately microscopically, you will ALWAYS have tiny rocks and wood fibers!
I havd explained this many times and nobody seems to understand it.
@@sylvisterling8782what does that have to do with algebra? Sure someone had to come up with the concept of algebra so in that sense it is made up, but math such as algebra has useful applications in real life. Without someone doing the math you wouldn’t have a device to even watch this video. So I guess I don’t understand your point about it being made up.
@@sylvisterling8782 c'mon dude, this ain't no abstract algebra course, it's a video on order of operations. Nobody seems to understand because you're explaining to others based on what you want to hear and not explaining in a form that will compel others to listen. You're basically explaining it to impress yourself, you're not necessarily explaining something because you want others to understand.
Algebra comes from "al-mukhtasar fi hisab al-jabr wa al-muqabala" the title of a book written by Abu Ja'far Muhammad ibn Musa al-Khwarizmi (which is also where the word algorithm comes from), colloquially its means "the reunion of broken parts". Originally, letters were not used represent unknowns, rather the algorithms used to solve problems were written out in steps, much like a recipe. Sometimes the algorithms were written out as poetry as a means to help better remember them.
This is arithmetic not algebra
Great video! I never could remember how to do these type of problems. After watching your video its perfectly clear…. And ive been out of school for 40 years! Thanks
To solve this expression, you need to follow the order of operations (PEMDAS/BODMAS), which stands for Parentheses/Brackets, Exponents/Orders (i.e., powers and square roots, etc.), Multiplication and Division (left-to-right), and Addition and Subtraction (left-to-right). In this expression:
3 * (5 + 20 / 2 * 5)
Let's break it down step by step:
First, evaluate the expression inside the parentheses:
5 + 20 / 2 * 5
Now, follow the order of operations within the parentheses:
a. Divide 20 by 2:
20 / 2 = 10
b. Multiply 10 by 5:
10 * 5 = 50
c. Add 5 to the result:
5 + 50 = 55
So, the expression inside the parentheses simplifies to 55:
3 * 55
Finally, multiply 3 by 55:
3 * 55 = 165
So, the answer is 165.
Unlesss you are a maths teacher, how on earth could you remember that rule? (I won't say you looked it up). I worked in pensions admin, actuarial, finance and insurance all my life but couldn't recall all that you laid out.
but the m comes before the d. so why dont you multiply the 2 x 5 first and then divide into 10?
@@johnbeard3733because the rule is you go left to right. Multiply or divide (whichever comes first), then add or subtract next (whichever comes first)
Thanks Peggy
Because he does not understand@@johnbeard3733
I got 165 and did it in my head. I was lucky to get a really good education growing up. I guess it comes down to the luck of where you live and which school you get to go to. Thanks for sharing this lesson.
The critical clarifying moment that you presented here is the insertion of the simple word "OR" in the PEMDAS sequence. I don't recall ever hearing it simplified that way by any math teacher back in the day or in any other CZcams presentations. I take my hat off to you in thanks, sir!
My teachers never got it to me either. They taught us how to do it but told us to go in order of letters, not multiplication or division. Multiplication, then division is what we were taught. I don't think my teacher was that skilled in math and just tried using the book with the answers in it. You can't teach somebody how to do something if you don't know how to do it yourself though.
This actually shocks me. I remember several teachers saying or. Another way of thinking about it is, if there is a run of multiple and division operations in a row, they all are acting on the first number.
@@brendanh8193 that's still not 100% intuitively clear. Left-to-right is necessary because division is essentially a fractional expression. 1 ÷ 4 and 1/4 is the same thing. Left-ro-right means you resolve the fraction into a whole number before multiplying by a whole number. If you go right-ro-left, you accidentally multiply the denominator by a whole number. The most intuitive way to understand this is 1 ÷ 4 × 5 is to convert it to (1/4) × (5/1). Now you're multiplying two fractions, (numerator × numerator) / (denominator × denominator). This is easier to understand when you have something like 1 ÷ 3 × 5. If you do left to right, 1 ÷ 3 doesn't resolve to a whole number. It's a fraction with repeating decimal .333333... Decimals are weird and confusing, especially repeating decimals. You run into problems of precision using them in calculations which is why representing them as fractional expressions is preferred, especially in equations with irrational numbers (pi, square root of 2, etc).
It’s even easier in Canada we were taught Bedmas. Which dosent allow for the mistake of doing the M first.
The important thing to realize is that division is just multiplication by the reciprocal and subtraction is just addition of a negative number. So really it should just be taught as PEMA and perhaps people would be less confused.
John, I love your math channel. I am a math person as well! Numbers & Math are the universal language. I think we should connect one day, I believe we would get along extremely well! Hope you channel continues to prosper!
Thank you so much for this! I totally missed the m or D and A or subtract. I totally understand it now!
Multiplication and division are of equal value and are done in the order that they appear in the equation from left to right; the same is true of addition and subtraction. It should be 3 x (5 + ((20/2) x 5)) = 3 x (5 + (10 X 5)) = 3 x 55 = 165.
I came in to type 165. You are quite correct.
PEMDAS is probably understood correctly in some countries.
BEDMAS removes confusion, where B refers to brackets or parentheses.
@@pandaycorpWe referred to this as BODMAS; Brackets of, Division, Multiplication, Addition, Subtraction.
@@pandaycorpI was taught BODMAS as the order of operations; brackets, order/exponent, division, multiplication, addition, subtraction.
Yeah, I got this correct answer on my 2nd try. I was trying to figure out using PEMDAS and of course that is incorrect.
I was taught Parentheses in order from left to right, then Exponents from left to right, then, Multiplication and Division in order from left to right, and finally Addition and Subtraction from left to right.
Addition and Subtraction were equal in that you don’t prioritize one over the other and same with multiplication and division, you just do whichever appears first so
3x(5+20/2x5)
3x(5+10x5)
3x(5+50)
3x55
165
I’m really not a math fan, but my favorite math classes in school were business math and data analysis & statistics. To me they were fairly simple and the teachers I had were amazing. The business math teacher was a very kind and understanding professor who was very good at explaining it so that you got it the first time and he didn’t even make us get the book, he just read from his own and we all worked the problems out together. My data analysis and statistics professor didn’t make us get the book either and he actually introduced a lot of humor into his teaching style, but he had that really dark and sarcastic type of humor like mine, but he was never mean about it and genuinely cared about helping you learn. With the war on teachers in this country the last few years I really hope they haven’t been burnt out by it, especially since I live in a deep red, but northern red state.
Thank you, thank you, thank you. I need practice. 👏🏻👏🏻👏🏻👏🏻👏🏻. So glad I found your channel.
Wow, your videos have shown me exactly where I stopped learning math around the eighth grade. (Where I was still getting in trouble for working the problems in my head.) I never learned PEMDAS, but it was not for a lack of people trying to teach me. I just didn't much care about school. Not knowing PEMDAS must be what doomed me to failure in pretty much all higher levels of math, I somehow passed algebra one, parts one and two, in ninth and tenth grades. I failed algebra two as a junior, and took geometry, (which I actually enjoyed and did well) as a senior. This is the third video of yours I've watched now, and the first one which I was able to answer correctly!
I'm 60 and had never heard of PEMDAS or wasn't listening in class. But after 2 previous videos I've watched of yours, I got this correct! Shocked and proud of myself. I wish you were my teacher 45 years ago!
Nicely done.
Wow! I hated math, but I remember PEMDAS. I specifically remember the mnemonic, Please Excuse My Dear Aunt Sally =PEMDAS! I teach it to my grandkids today! My granddaughter is gifted in math & way ahead of her peers! She's 10. Proud grandma here, sorry! 🤭
Same, but I know I was never taught this,which would have made maths lessons so much easier……# sigh
I am older and we were taught the rules for equations; however it was never referenced as PEMDAS or any other acronym. We just remembered it by the function names.
We were taught BODMAS. I too have never heard PEMDAS
42. The answer to everything in the universe .. except this. It's 165
3(5 + 20 / 2 x 5) = 3(5 + 10 x 5) = 3(5 + 50) = 3(55) = 165
Another method to help you with PEMDAS (or confuse you more ;-) ) is keeping in mind that a **division is just a multiplication of the inverse value or reciprocal so that will transform your problem to: 3 ( 5 + 20 * 1/2 * 5 ) or 3(5 + 20*.5 * 5) , so now the division disappears and you do left to right multiplications in order first. 3 ( 5 + 10 * 5 ) => 3 * (5 + 50) , 3 (55) = 165 or when you are down to 3*( 5 + 50 ) , you could use the distributive principle you use in algebra of a (b+c) = (ab+ac); (3*5 + 3*50) = (15+150) = 165 to verify that you answer is right. Keep in mind that PEMDAS is just a trick for your to remember order of operations, but as you learn more math there are other tools that will help you gain speed or find easier ways to solve problems that might be more relatable on how your own brain works. This is fine example of how simple arithmetic is a foundation block for algebra, geometry, trigonometry, pre-calc + more. **Note: this is mostly true with integers and rational numbers, you run into some issues later in life in computing, software, with irrational and imaginary numbers like pi. :P
a faster way to do this in this example is
3 ( 5 + 20 / 2 * 5 ) = 3x5 (1+10) = 15 x 11 = 165
Thank you, this is great. I don’t really need it, but I love knowing how to do it. Even though I could have used it 45 years ago.👍🏻
Got this one right, even though math used to be my worst subject ^-^ After getting a very bad grade at algebra, I started practicing it alot and actually started to enjoy it alot. Eventually I got one of the highest grades of the class and was alot of fun, like just making puzzles. Glad to see some still stuck ^^
Yup, immediately realized people get it wrong because they're doing the addition first.
Wow, I just realized how much I had forgotten in regards to basic math. Thanks for the video. I got it totally wrong. I worked left to right in the parentheses, then multiplied by 3.
I did the same thing. Why wouldn’t you just put them in order of how you’re supposed to work it out?
That would make sense, but I remember math had it's own set of rules. I just pretty much forgot all of them.@@Inquisitor_Vex
My lord if you were my teacher I would be great at math. Your voice isn't threatening and your teaching is superb.
I commend you and I thank you for posting your knowledge and your spirit comes through to teach younger people and adults like myself how to properly understand math. I applaud you, your parents and all of your teachers. 👏🏿👏🏿👏🏿👏🏿🎉😊
My son had a young lady fresh out of teaching college who taught high school math. She was awesome. He was an engineer.
Agree ... we need more efficient teachers. I have a friend who is becoming a teacher and she can't spell. That immediately limits her effectiveness as a teacher.
@@nukasnook1561Nothing worse than an illiterate teacher. I had an English teacher about 50 years ago who couldn’t pronounce Yosemite, she called it Yo-see-mite but she was thankful when I told her the correct pronunciation Yo-sim-a-tee.
@@JohnFourtyTwo Another way of saying "Yosemite" is "the most fabulously beautiful place to visit" - especially in the months of May and June when the snowmelt fills the waterfalls and Merced River. Great that you taught the teacher how to say the name of this most wonderful place.
Heh I live in New Zealand and I know the correct rendering of Yosemite.
Appreciate this content! Wholesome, true, and even though I got 21 initially: you were not condemning.❤
Likewise here...
Thanks for doing this. Very good lesson, nicely taught.
I am actually quite proud of myself. NO ONE could ever make math make sense to me in school; At first I solved it incorrectly but as soon as I saw it written with a proper division sign opposed to the forward slash, which I also recognized as divide; I knew to do the division before the multiplication and got it right. And all in my head. Major accomplishment for me!!😀 I'm quite sure I couldn't pass a grade 8 math exam though....
Practical comment: As a 35+ year engineer… just use extra sets of parentheses. Or break it up into smaller parts. Or both. Other people may be looking at your work. Regardless of the correct “rules” it’s better to clearly communicate what you are doing … don’t assume that the other people know the rules as well as you do.
"As a 35+ year engineer… just use extra sets of parentheses."
And then everyone would get the same answer and it would not be clickbait. There's dozens of these videos with minor variations so we can argue about it.
@@thomasmaughan4798 they are nice, though, but of little practical use.
Very true, be explicit in how you want the problem to proceed. The best way is to design the problem so that it will give the right answer if it is fed into any computer on the planet. If it will not, then clarify.
As a fellow engineer, (since Mar 1980, 43 years 5 months) I totally agree with you, I haven't even watched this video yet but I can clearly see that the equation is very poorly expressed. Just the part inside the parenthesis can be solved as 55 or 7. I'm leaning towards 7 because the video description shows 3 times ( 5 + 20 / 2 x 5 ) and because it's expressed as a fraction, you should solve the denominator first. Then, you have 5+20/10 or 5+2=7 Making the overall equation 3(7) or 21. Now I'll watch it and I'm probably wrong. Yeah, according to the video, I was wrong. But the fraction 20/2X5 does equal 2 and then, 5+2=7. At least he admits that math teachers do try to trick their students. He says it's to see who was paying attention in class, However, he doesn't go into the actual psychology behind this, which gives you the real reason, they do it to boost their own EGOs. They do it to feel smarter than their students, by tricking them. Tricking them doesn't make them better teachers. Rather, it allows them to ease their own inferiority complex and feel better about themselves (probably because they were called nerds, or geeks, so often in high school). It has nothing to do actually with teaching the students. I hope he was able to boost his own EGO with this video and then, he can feel better about himself. 3(5(20/2)+5) would have been a much better way to express the intent of this equation. It communicates the intent more clearly because you're not trying to trick your intended audience. I gave your comment a like. Have yourself a great day!
Spot on!
From left to the right. First operations in brackets and point befor line operations. We dont use the cross for multiplikation. We use a single point. Division we dont write the line in between the points.
I really appreciated this refresher.
Really enjoying your content. Your content is cool because I am a school teacher. Your content makes for good conversation with the other school teachers. I learned something new today. Thank you.
Very simple 21…. Accomplished in under 20 seconds
Learned PEMDAS from you yesterday and solved this one quickly!
What program are you using for the screen/writing on the screen? I've been using Windows Journal which is no longer supported and haven't found a stable replacement for it. Looking at your screen it has most of the features I use journal for (maybe having grid-paper as the background is missing) so I was just curious.
Saw the video title and image, did the math in my head, went to the end of the video and....kudos to my elementary school teachers. Whatever you did, it stuck.
I found maths very challenging at school, but I LOVED this video - got it wrong first time, but I learnt a lot!
Great explanation - wish you'd been my maths teacher!
The teacher you have makes such a difference to your learning skills, some can impart their knowledge and you totally get it.
Never too old to learn though. 👍
“Maffs” that’s you
@@mikeb8013 not exactly...I'm an English teacher, and my pronunciation is pedantically clear and precise!
My sister loved math for the same reason you have. She liked the challenge. In contrast to my philosophy, I woke up every school morning conceding defeat in every aspect under the title "Schoolwork". Lol
@NA-fe4yy both are correct. In the UK they say maths. In the US, we say math.
I didn't enjoy math in high school, but I only had basic business math. When I stated college part-time, I had to take pre-algebra and learned to love quadratic equations. BUT outside of school and the fields of science and engineering, does this truly matter. I must say that after taking my math classes required with my degree, I never needed to use it again.
In the Netherlands, the answer would be 21. Unless they changed the rules. The formula in which order to solve this over here is (was?) Meneer Van Dalen Wacht Op Antwoord (literally translated Mr Van Dalen Waits On Answer) : Machtverheffen (not applicable here), Vermenigvuldigen (multiply, so 2x5=10), Delen (divide, so 20/10=2), Worteltrekken (not applicable here), Optellen (add, so 5+2=7), Aftrekken (not applicable here). So we end up with 3x the 7 from within the brackets, equals 21.
You would divide first because that's the first order of operation within the parentheses from left to right, after you would multiply.
Simply no.
PEMDAS is misleading. Multiplication and division are equal level. Here its left to right.
Its that simple. Same allpies to addition and substraction: same level, left to right.
Any one familar with programming languages knows this.
@@dilbert0815 PEMDAS also neglects Juxtaposition (implicit multiplication) which leads to ambiguity and wrong answers.
PEMDAS: 6/2(1+2) => 6/2(3) => 3(3) = 9; which is incorrect but what most U.S. calculators will yield.
PEJMDAS: 6/2(1+2) => 6/(2+4) => 6/6 = 1; which is correct.
For those in doubt 1 is the correct answer visit the site alcula and go to the RPN calculator enter the following: 6, enter, 2, enter, 1, enter, 2, +, *, /
Actually you just mess up the order the same as the rest of the world leading to a wrong answer of 21. Man I hated getting those papers back with the red pemdas written everywhere.
We were never taught about 'left to right', so the answer would still be 21. Good thing everyday life doesn't have to deal with this kind of nonsense. ;-)
I finished high school with mathematics as a chosen, and never needed it after my graduation. So, as far as I am concerned, the answer could be 3,000,000.
I’m 61…(gasp) and someone along the way, taught me this…but I didn’t retain it. Today because of your video, I believe I got it! Pemdas! Love it…thank you.
Sure wish you were my math teacher back in the day. Now I lament that I can’t do math and my brain cracks. I enjoy your videos. I don’t feel that I am not capable. Thanks.
I'm really glad when I see these problems in my feed and I get them right :)
The world (and CZcams) really needed another PEMDAS video
3[5+(20÷2)×5] --> 3[5+(10×5)] --> 3(5+50) --> 3×55 = 165
ya took me less time than you to write that.
I agree, this is basic order of precedence.
@@weebee6922me too.
Thank you
I am so excited! I got165! YES! I do not remember being taught this loooooong ago! (I remembered it from one of your previous videos, I think!). Thanks!
Got it this time! Yippee!!...❤...
I didn't have a good math teacher until my freshman year in college. For years I had struggled with math, although I had the GPA I needed to be accepted by the university. This one professor cleared up the mystery...from that class onward, the rest of my classes were a snap! My 8th grade math teacher was also helpful, but I still had headaches with math. My freshman math prof made all the difference.
Thanks for sharing this information
I've got to review all of this stuff since I have a four year old grandchild that is exceptionally bright and all to soon he will be wanting to learn. In my view this guy is just what the doctored ordered. I don't know that he would agree but I've found that fifty per cent of learning Algebra on up is just learning the formula!
I did that totally wrong by addition first and dividing the sum by the multiplied sum. 3(25/10)=7.5. That’s quite a difference. Thanks for reminding me of the order.
Me too. 7.5
@@alicejackson7676, I thought I was alone. It’s so nice to have company. 😁
That's exactly the way I was taught back in the 60s and 70s and I still think it's the right way. I nearly always get different answers to this guy.
This is the way i was taught at school. After four decades in business i never get my figures wrong. I would be interested when and where the maths was changed.
That’s what I got too. 7.5
Where did the rule for M or D whichever come first from left to right even come from? How is it so many teachers go it wrong for generations? Was this recently invented or recently discovered?
Even is the US, the order of operations, even when using PEMDAS, is not universally taught. Some teachers say multiplication goes before division and addition goes before subtraction without regard to left-to-right. Which is right depends on whom you ask. Confusing.
I was taught PEMDAS (Please Excuse My Dear Aunt Sally) and got 165.
3(5 +20/2 x 5) =
3(5 +10 x 5) =
3(5 +50) =
3(55) =
165
Edit: I was taught PEMDAS in 6th grade and reminded again in Algebra
I got it right to! 😉👍=165
I was never great at math and I as well was taught this in 6th grade and my achilles heel Algebra as well. So proud of myself I got it right too! And remembered it!
I thought it was BEDMAS- BRACKETS EXPONENTS DIVISION MULTIPLICATION ADDITION SUBTRACTION. There is not a aunt Sally in math. At least it is in Canada
3(5+20/2x5)
PEMDAS
Inside parenthesis
Parentheses: ...
Exponents: ....
Multiplication: 2x5=10
Division: 20/10=2
Addition: 5+2=7
Subtraction: ...
Outside Prentheses
P: ...
E: ...
M: 3x7=21
D: ...
A: ...
S: ...
The answer is 21.
BODMAS
brackets
Of. As in ‘power of’
Division
Multiplication
Addition
Subtraction
Following these rules, I got 165
I know BODMAS is different to BEDMAS or PEDMAS, but it means the same thing and I’ve remembered BODMAS for 40 or more years! So my teacher managed to jam this into my head that’s lasted almost half a century
I have been a machinist and a fabricator and a carpenter in my lifetime and I’ve never run up on one situation where I used any equation like this. I couldn’t figure out in school why they were teaching me this and now I’m 52 and still don’t know why.
You might think you have not have used what you learned in math, but you've probably used the logic and problem solving skills you learned without realizing.
@@rthompson7282 It's not so much the basic math is of no use. It's that writing a practical problem in this way is something a non-mathematics professional would never do. Effectively as he mentions around 10:25 it's made in a way that is intentionally deceptive. In most practical applications of math, you end up being held accountable for the result of the use of the math, so if something is written in a way that could seemingly done multiple ways and the wrong one is chosen, liability for the outcome becomes a concern. Mathematician's don't have this issue. Like @larrybuckner8619 mentioned, machinist, fabricator, and carpenter, his head or a coworkers head would be on the chopping block should something unfortunate happen due to writing an equation in this way. At best, this use of presentation in math, is a good example of what NOT to do in terms of learning logic and problem solving skills, because it eschews common logic and practical use in favor of requiring rote memorization and convoluted presentation to create a problem in need of solving, neither of which is of any direct practical use.
the beauty of mathematics and how finite it is in a disorderly society has an appeal. wish i was better at it but i do understand the appeal
If you would have done an electrical apprenticeship, you'd understand why...
Me too . I worked in dentistry and never used it , not in the last 22 years anyway
Thank you for the correction because I originally got 21 but at first I was asking the same questions should I divide 20 by 2 or multiple 2-5. After you explained it that’s when I remembered that we’re supposed to move from left to right.
Don’t just memorize a rule, understand that division is really just multiplication by a reciprocal (1/n). You don’t need to go left to right, because it literally doesn’t matter what order you multiply in.
It depends how in-depth you want to take it. The actual answer is 1
Look at the question ' what is first? '
of the 3 digit answer 165, the first digit is 1
Great video. You are correct in that this lesson in breaking down PEMDAS doesn't get discussed enough.
Please Excuse My Dumb AS
P-E-MD-AS should die since it neglects juxtaposition and leads to ambiguity. It should be replaced with P-E-J-MD-AS
Consider the following simple equation: 6/2(1+2)
P-E-MD-AS: 6/2(1+2) => 6/2(3) => 3(3) = 9
Reverse Polish Notation: [6, enter, 2, enter, 1, enter, 2, +, *, /] = 1
P-E-J-MD-AS: 6/2(1+2) => 6/(2+4) => 6/6 = 1
Plus and minus come in which ever order they come first
X and : come in which ever order they come first.
In this, here is the 4 second easy calculation that ran in my head:
20/2=10
10x5=50
5+50=55
3x55=110+55=165
That’s what came into my head right away too.
Thank you Mesiah. I have finally found someone who has taugh basic arithmetic to me!
The order of plus and minus doesn't matter
Im an electrician and im always confused with plus and minus
In early teaching, ÷ said any function to the right first then the ÷ so 20 ÷ (2 x 5).
Delirious here. Got it right! You’re a great teacher, but I needed clarification and listened to another educator who said we always move from left to right and m/d means either procedure , but if division comes first, do division.. you’re good, thank you! Wanna give us some homework?
Inside of parentheses first.. div and mult before add and subt. .. working left to right. Then multiply by number outside of parentheses. PEDMAS OR Bodmas PEMDAS or Bomdas. SAME THING
I'm 75 and terrible in math but I'm doing these to work my old brain. Thank you!
I got 65
75 .. your a kid😀😀
Thank you teacher! I'm a frenchman of 71. I never heard about PEMDAS or equivalent in french before you spoke about it! And though my english is far to be perfect, i understood your whole explanations and i'm very glad of this. I have to precise that when i was young, i hated mathematics and the teachers in this discipline. Now i notice that i understand very easily, and in english! So i have to consider nowadays, that i am a little bit smarter than a nut... What a great satisfaction !😊😉
12765 .......ahh close, but no sigar
@@RS-Amsterdam ???
I believe other teachers I forgot where teaching B.O.D.M.A.S rather than P.E.M.D.A.S
@@alfredvikingelegant9156 🤪
La première fois que j'ai appris l'ordre des opérations, c'était en français, mais je viens des États-Unis. Mon école primaire avait un programme d'immersion, donc mes cours de mathématiques et de sciences étaient tous en français pendant cinq ou six ans. Quelle coïncidence intéressante ! (pardonnez-moi s’il vous plaît d'utiliser un programme de traduction, mais je fais encore moins confiance à ma grammaire sans lui. Cela fait longtemps que je n'ai pas pratiqué!)
I thought the answer was 150. I missed a step. Lol. Your a God send im so happy i found your channel. Liked and subscribed 😊
Great teacher. Thanks for your teaching.
I love this!!! Back in college, I majored in math and I love solving problems so this was easy for me. Needless to say, my nieces and nephews and grandkids all call me when they need help with their math homework - because according to them, I explain it "way" better than their teachers can! However, trying to help them solve complex math problems over the phone is a pain - especially when I'm at work or at the grocery store! Because well, when solving any math problem, it's all about the visuals!
Sadly, I'd say that 95% of people who think they're bad at math, really aren't. They've just never had the benefit of a great math teacher to visually explain the proper steps to follow when solving a problem. I tell my grandkids to always follow each step and that a single problem can take up to a half a page to solve, and extremely complex problems will take up the entire page - front and back! Knowing the proper steps and following those steps exactly, will ensure success.
After watching your videos, I have to tell you that you sir, are a fantastic math teacher! Not only is your voice very calming, your visuals are the best I've seen! This is exactly the way I have shown my kids and grandkids how to solve a problem - only this is better! Your use of the green "chalkboard" style screen, combined with your use of fonts and explanation of proper procedure is extremely effective. It's so easy to understand, follow and comprehend. I just forwarded your channel to my entire family!
The kids will be starting school in a couple weeks, so I told their parents to subscribe to your channel and to start watching one or two of your videos every day. I told them to make a game out of each video by having everyone solve the problem on their own, then watch the video to see who got it right! By turning it into a game, it makes it fun for the entire family and the kids (and parents) get a refresher course so they're prepared when they go back to school - creating an everlasting boost to their confidence. I'm so thankful I found your channel. You are a Godsend to both parents and kids who struggle with math! Your channel is a game changer! Thank you so, so much! 💙💯
answer is easy 21
I used to find I didn't understand the way our teachers explained things - this was New Zealand in the 1970s - but I easily understood the way my father explained how to do the equations - he was taught in England, 1930s/40s. I don't understand the modern ways at all and I not only enjoy maths/arithmetic but am generally fairly good at it - don't like using calculators though - and I can't understand why people now say that the ways they were taught in the UK as kids give different answers to those I get because my dad was educated there and the ways he used and taught me were the same as our teachers used in NZ, but which now appear to be totally different to those taught in the UK. Very confusing and can only guess they changed their teaching methods some time after the 1940s for some reason.
i only read like 2 sentences but i’m gonna go ahead and guess you’re a english major also cuz damn that’s an essay.
When a teacher asked me to explain why something's done in a certain way, my only response was "because you said so". Beyond basic arithmetic, math makes absolutely no sense (and I was never good at word problems, even in basic arithmetic). I majored in Computer Science in college, but I wasn't able to take any programming courses because I couldn't pass Algebra. (Well, I took JavaScript from another college based on a technicality; the professor didn't know why I was in the class since I was already good at JavaScript, but I thought it would be an easy elective; I got in a tiny argument because the textbook said to use document.write() in an XHTML document and brought up that write() is part of the HTML DOM but not the XML DOM so you have to use methods like createElement(), createTextNode(), and appendChild() to properly add new content to an XHTML document (eh, I did it properly regardless of what the textbook and the professor had to say about it)).
When i did math in the sixties the way this is written the answer would be 7.5 . We were taught to figure inside the parentheses first. 5*20 =25 divided by 2*5 =10 answer 2.5 *3 =7.5
I forgot. How do you know that the 3 in front of the parentheses is multiplied by what's in the parentheses?
since / and x and inside () is first it should be kinda read done like this.. 20/2 = 10, 10 x 5 = 50, 50 + 5 =55 and lastly 55 x 3 = 165
If you see the parenthetical part first and then see not a division problem, but a fraction: 20/2, it works out. 3[5 + (20/2) * 5] =. It's a good idea to always think of a division symbol to mean a fraction.
Not a bad idea, but not flexible enough.
Let's say we change the question to 3(5 + 20 / 2 X 5 / 10), thinking of it as a fraction might add more confusion like 3(5 + (20/2) x (5/10)) while the correct form would be 3(5 + ((20/2) x 5)/10). It works out but also add some complexity.
Easy calculation straight you get 165 with this nicely bracket in there
I was never taught any of this and got 187.5. Thank you for the lesson!
Yikes we must be on a similar brainwave as I got the same answer as you when I did it before watching the actual video.
That is what I thought is that correct?
Agree with this number
This is the same # I got as well
@@hcox1111No
It would be interesting to know if you read, or better yet. Listened to Cormac McCarthys last tw books.
Mr tablet maths what makes you say that many wont get it right
Simple and easy explanation! Plus a nice refresher for anyone who’s forgotten the PEMDAS formula.
Here in the UK the pneumonic I was taught many, many decades ago for solving mathematical problems such as these was BODMAS - Brackets, Order, Division, Multiplication, Addition, Subtraction. Using it got me to the correct answer here.
That pneumonic, along with many others, just stuck in my brain. I’m in my sunset years now and when old age senility kicks in the one thing I can be sure of is that those darn pneumonics will still be there; even if I don’t recognise my wife 😂
I can never remember where I parked my car, but I know all the words to the theme song for Gilligan’s Island, so I’ve got that going for me.
Mnemonic = device to aid in remembering something
Pneumonic = something affecting the lungs/related to pneumonia ;)
@@Kernel15 Ah well. It would appear that my old age senility thing kicked in earlier than I thought 😂
BODMAS for me too! (UK comp '72 - '79). I'm 62 🙂
The mnemonic I learned was "Please Excuse My Dear Aunt Sally, who wobbles From Left To Right". That is PEDMAS, From Left to Right. Learned this back in the 90s.
GREAT LESSON!
And here I am, 48 years old and still made this mistake. I had a hard time with Maths as a child therefore hated it. I learned today what I have some 40 years ago 😂 thanks!
Find your teachers and tell them: it's ok, you didn't need to know it .
One should be careful to judge just from a single comment. But it sounds to me like you had a hard time in math because your teachers spent time drilling pointless and pedantic rules like division versus multiplication, rather than focusing on actual math.
I have to use the Multiplication or Division and Addition or Subtraction (which ever comes first from left to right). That made a huge difference in the outcome. I was never taught that rule in any math class I took ever. Thank you for sharing.
Yes, you were taught this. It is in every math book for many decades
@@willh1655 I was taught the PEMDAS method, however I was never told it was one or the other, from left to right for the MDAS. So, I would get a good portion of them correct, but didn't have that one piece of the rule in my brain.
The thing is left to right, right to left, or no order at all; order should not matter. If it matters the function is written incorrectly. Its stupid high school math teachers with education degrees being too smart by half. Associative property says you should be able to change the order however you want without affecting the result. This is fundamental to real math and how actual smart people solve extremely difficult problems, you reorder, distribute etc. and reduce the function. These high school math teachers just prove why US education sucks.
@@chonzen1764 More like to smart by double. They can't even get their simplified calculation courses taught correctly, nevermind actual math.
@@Llortnerof I have a generally low opinion of education majors. When I was in my undergrad and on athletic scholarship all the guys on my team who wanted to drink and party would change majors to education because it was so easy.
An exception was those on the team who seriously wanted to be high school coaches and chose education as their 1st major. They were usually extremely intelligent and knew they had to be teachers 1st if they wanted to ever become a head coach. Teachers union usually requires that teachers priority on coaching hires. That and its damn near impossible to run a successful program if you aren't in school.
I always used the acroymn called BEDMAS. B for brackets, E for Exponents, then division, multiply, addition and finally division
Instead of PEMDAS I taught my students PEMoDAoS, the little "o" stands for OR, when confronted by the same level of operation the one that comes first working left to right (the same direction we read) is the one acted upon. I had the kids make up their own sayings to remind themselves, the best was "Perform Each Math Operation During Algebra On Schedule". When the kids become invested they own it!!
Brilliant ! Your students mnemonic makes more sense than any others I've seen. Congratulations. You are the kind of math teacher that can open their minds to the joy of numbers! I salute you.
I actually teach science but I took a lot of higher math since it was physics and knew the answer. I am going to put this in our staff zoom chat to see who in the math department can figure it out.
Remembering the rules of pemdas and not overthinking it, I came up with 165 in my head in about 20 seconds.
I’ve noticed people forget that addition and subtraction are equal, as are multiplication and division.
Tu solo lo haces MAS COMPLICADO; MUCHO BLA,BLA,BLA,BLA,¡¡¡¡
Not true. This guy got it wrong!
Depends where you live. In Australia we use BODMAS (Brackets, Operations, Division/Multiplication, Addition/Subtraction).
No it definitely doesn't depend on where you live. The rules for solving mathematical operations are universal.
@@mrkiky it depends on what you call it, but yes, the rules are all the same.
Is there a difference between the American way of doing this? Then those that use metric system? Because I got the problem correct, but using our way of BEDMAS, where Brackets > Exponents > Division > Multiplication > Addition > Subtraction
If anyone out there knows, let me know.
The problem with PEDMAS or BODMAS or any other pnuemonic used for order of operations, there are times when parenthesis should be utilized to eliminate ambiguity whenever possible since algorithmns will vary given the slight differences in the order of operations computing methods.
Canadian who learned order of operations back in the 1970s. My school didn't bother with any mnemonic device at the time, which may have been a good thing. Always clear to me that multiplication and division had equal priorities with each other (as did addition with subtraction). The PEDMAS mnemonic sounds as confusing as it is helpful, which, when you think about that, means it is a HORRIBLE mnemonic.
tbf, we learned it as BEDMAS (or BODMAS, depending on terms used) in the 90's and that was a perfect layout of the order of operations. Also, when did PEMDAS become the new norm and who needs to be flogged for messing up something so simple? Or was it keeping in line with the overcomplication/revamp of basic math they did at one point?
Also Canadian, but we were also taught MD in the order they appear, and AS in the order they appear. I don't know if they still teach that way but it was cemented in our heads from grade 6 on (learned in 90s). Also why make such a big deal over P or B? Parentheses are Brackets. It makes no difference. Also if you were taught in the 70s you probably learned with BODMAS Brackets Orders Multiplacation and Division (in the order they appear) Addition and Subtraction in the (order they appear). My mother and father taught me BODMAS when I was 8. By time I was in highschool it had become BEDMAS (as exponents made more functional sense as a term then Orders) ....they learned it in the 70s as BODMAS, so you would have to.
@@TheTicoune Since the internet spread Americana to everyone. BEDMAS is popular in British English Schooling (Canada, New Zealand, Australia, UK), where as PEDMAS is an American spin on it because despite being anglophone they choose to be different. They are the exact same thing. Parentheses = Brackets.
@@kurtmooreca PEDMAS would make sense, but its not spelled out that way for whatever reason: PEMDAS is the official way...even though it makes no sense and creates confusion rather than helping it.
@@TheTicoune Why would it make more sense to say division before multiplication? These 2 are equal, you dont do either one specifically before the other.
Got this one pretty quickly in my head. I'm the one who teaches and or helps out our kids with math and order of operations is so important!
5x3 example: 5 apples to make a pie. *Need* to make 3 pies. Seems to me that passing fifth grade math is all you need to get through life after school. *How in real life would the equation in the video be necessary other than to employ math teachers?* I understand that math has rules for a reason but can you give me an example to *NEED* the equation in this video?
@@jacka55six60 in most of our lives no. Basic grade 5/6 math is mostly enough. In the professional world though, such as engineering I know they are required to do far more complex mathematic than that simple equation. Never mind if one gets into astrophysics or orbital mechanics. So I don't think it's just to employ math teachers no.
Since multiplication and division have equal weight, I did the 20÷2×5 part from left to right to reduce that to 50. Then I added 5 to the resulting 50 inside the parentheses to reduce that to one term, 55. Then just multiply the 3 on the far left by that.
The answer is 165.
Clearly does not have equal weight. If they had equal weight, you could multiply first in the "20/2*5", get 2 as a result and you would be right. You would be wrong though.
@@seph. Yeah they do have equal weight. But you always solve from left to right. Therefore you do first the division and then the multplication. (20/2*5 => 10*5 => 50)
@@nIghtorius shouldn't i be able to solve right to left, if equal weight?
@@seph. when equal weight you solve from left to right.
@@nIghtorius i want to do right to left though. Equal weight, so shouldn't matter.
It concerns me that on some other ‘Math CZcams’s’ they have Engineers (Chem, Nuke, Elect, etc) that totally disagree with PEMDAS Method. PEMDAS is the first thing I’ve ever been able to grasp.
Please Help 😮😢!
wish I understood this when I was in school. Thank you for explaining it.
This is the first video of yours that I have seen, and I WILL be subscribing just to try and re-learn what I've forgotten from 9th grade Algebra I in 1973. I struggled with math beginning in 4th grade. Our teacher was Asian, his IQ was probably at least 200, the whispers in my class were that he could make a perfect circle on the chalk board, and they were right. His accent, his IQ, and the speed of what he wrote on the blackboard was faster than I could understand, and he didn't repeat things. That was my first year of fractions, and with each year after that, I struggled so hard, and when it was time to sign up for classes in 9th grade (still junior high) for math, there were 2 options. General Math or Algebra I. That was an easy choice for me, General Math. On day 1, I was nervous and happy all at the same time because I felt like it was something that would be easy for me. Sort of like some of my other classes were. My teacher was probably around the age of 60, and very easy to pay attention to. After day 2, he asked me to stay after class, and I was petrified. I went to his desk as the class emptied, and he asked me "why did you sign up for this class"? I hung my head (I was terrified of my own shadow) and told him of my difficulties with math and that I thought I would do better in General Math. He then told me that he also taught the Algebra 1 class, and he was sure that I could do it, and he wanted me to give it a try, and if I couldn't do it, I could go back to the simpler math. Having him tell me that he thought I could do it was something I wasn't very used to hearing, but I went to Algebra I the next day and I stayed in his class, never getting below an A- on anything. I was even raising my hand to answer questions-that was new for me also. That man made me believe in myself more than any other person in my life including my parents. So for High School, I joined my classmates in Algebra II. Totally different teacher, and I fell behind quickly. I barely got through the semester without failing, I dropped it after that first semester, and never took another math class. Little did I know how much math would be part of my life for 18 years of working in Ophthalmology. It was only dealing with positive and negative numbers, but I could rattle those numbers off, I had a great understanding of how crucial my numbers were for the surgeons, and while I never needed Algebra II, I climbed the ladder to the top rung one step at a time, always grateful for that one teacher who believed in me. Sorry for the book, I will sub you now that I've learned something from you. Your voice is calm just like my teacher who I wish I could have thanked for what he did for a farm girl who didn't think she would go far in life, but I did. God bless good teachers everywhere.
Easy. In the parathesis, begin with the multiplactor in the order left to right. I found 165 really quick.
Can you explain to me how this is practical in a life situation?
I got 165 too, we were taught BODMAS at school. Brackets, orders, Division, Multiplication, Addition, Subtraction.
Same, but I learned BOMDAS 😅
@@gravyz2cute4u Which just shows you, It's just an agreed method.
Interesting- in Canada they teach it as BEDMAS. (B standing for brackets or parentheses) and the rest is the same as this version. My husband taught math for 30 years, so I heard this a lot!
I learned it in elementary school. It’s impossible to forget so I don’t understand how so many don’t do this right.
It’s PEMDAS here. P for parentheses lol :)
@ScrewyDriverTheMan It could be BEDMSA or PEDMAS and it would be right as MD are equals and AS are equals and are solved from left to right in the equation
@ScrewyDriverTheMan The DM is not backwards since the ordering doesn't matter. MD and DM are correct as long as you read the equation from left to right. Their here is probably referring to the USA. USA typically does PEMDAS while places like Britain and Canada use BEDMAS.
@ScrewyDriverTheMan PEMDAS is not wrong, its just a different way of saying it. Like he said in the video, multiplication and division, as well as addition and subtraction, are groups and are done left to right. You don't have to do division before multiplication, you do them in the order it shows up in the equation. He just happens to have the division first. If he had the multiplication first, you would do that before the division.
The other correct way is to use the transitive property with the paratheses. So 3(5+20/2*5) = 15+60/6*15 Then finish with the MDAS. 15+10*15 = 15+150 = 165
when applied properly math problems can be solved using different techniques - for me I try to simplify as much as possible so that the problem does not require a lot of calculation
3 ( 5 + 20 / 2 * 5 ) = 3 * 5 (1 + 10) = 15 x 11 = 165
I’m not especially mathematically inclined except in music theory and composition but took calculus for my mba in finance in 2015. I earned 2 grad degrees in my 50s while working full time as an accountant and part time as an organist and music teacher. I should know all this but have not used it so…but got this correct. Miracles happen.
When you express the division operation like a fraction it is much easier to see what should be done first. Placement of the division bar makes it much easier to see different groupings than the elementary school division symbol you used in the original expression.
I think when I went to college I rarely if ever saw the elementary school notation. We always used a fraction bar that you could position so as to minimize any ambiguity.
Also when my teachers taught PEMDAS, they always made it clear that multiplication was first and addition was second and each were performed LEFT TO RIGHT.
If it is rendered as vertical fraction, with a horizontal line through the middle between numerator and denominator, which clearly shows the extent of the overall fraction, then yes definitely. But fractions are more likely to be renedered in typed text with a 'front slash' which is no clearer than using the division symbol used here.
@@MrDannyDetailin which case use parentheses to do the grouping that would normally be represented by the positioning of the numerator/denominator. If you were writing this in LaTeX you'd have to use those parentheses anyway.
Amazing. I really don’t remember that method of working. Low math grades but was never told why I was getting it wrong. I just felt stupid. It affected everything! Thank you 😊
I have been in so many math classes in my 44 years of life, including years sitting in with students who needed a note taker as a class accommodation. I don’t think I have ever heard this, and now I actually understand why I majored in German and Spanish instead of Environmental Science since I could never pass College Algebra. 😭 It’s kind of sad when something is finally explained to you and shows you a huge reason why you were struggling so much in a subject for so long, especially when it’s something this ridiculously simple. You can know all the correct formulas and still never get the correct answers if you are missing one foundational explanation. I remember asking “why” questions in algebra and being told, “Because that’s just what you do.” If only someone had just told me it’s because those four acronyms were two groupings rather than a strict rule of order.
I wish every student had a teacher like this in their lives.
What is the symbol after the equals sign?
That's interesting. When I was in school in NZ we were taught BEDMAS (Brackets, exponents, division , addition subtraction). Which is slightly different to PEMDAS. But then if MD and AS are equal and you go left to right in that PEMDAS instance it doesn't really matter which you use, I still got the right answer of 165.
23 years since I have had to do any Algebra. I was stuck until I got to the PEDMAS part. Had completely forgotten how to do this. It is true if you don't use it, you lose it. I will be digging through these videos as a refresher course.
Hahahaha…PEMDAS
Paranthesis
Exponents
Multiplication
Division
Addition
Subtraction
Algebra?
Yay, I got it right! I remembered to do MD before AS within the parenthesis first but I had forgotten the left to right rule. I just naturally did the left to right because it seems to be the thing to do. In my mind, I guess I just subconsciously think, why would I go right to left when I do everything else left to right lol. (Reading, writing etc)
If this is posed as a question or part of a spec…. It would be rejected. Not enough information. Either provide a complete precedence list for the operators or rewrite in rpn.
On the other hand , should the persons taking this test, first agree upon, the order of operations? If there is no agreement in advance, left to write is the default answer, why or why not?
7.5
I got 750 so your answer makes the most sense to me.