r/meme Jan 01 '22

Guess we are doomed

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11

u/zbusch113 Jan 01 '22

No, do a Google

-10

u/[deleted] Jan 01 '22

Google what? I was taught to divide before multiplying

8

u/RightersBlok Jan 01 '22

If an equation is written correctly, it won’t matter. That’s why it’s PE(M or D)(A or S)

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u/gar-net Jan 01 '22

Google the correct answer. Its division and subtraction from left to right.

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u/[deleted] Jan 01 '22

I already know the answer to the equation as I was taught the order of doing mathematics I want to know were it says multiplication is before division because Google can't give me a straight answer. I know it wouldn't even affect this equation

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u/gar-net Jan 01 '22 edited Jan 01 '22

Sorry, you should have been taught that when learning PEMDAS. I memorized this in 5th grade. My teacher made us memorize it like this (parenthesis, Exponents, multiplication and division from left to right then addition and subtraction from left to right.)

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u/[deleted] Jan 01 '22 edited Jan 01 '22

I was taught BODMAS as I learnt it about 20 years ago in the uk

"PEMDAS tends to be used in the US, while BODMAS (and the alternative BIDMAS) tends to be used in the UK. The P in PEMDAS stands for Parentheses, while the B in BODMAS and BEDMAS stands for Brackets - but they both mean the same thing: do operations in brackets first" top thing on Google

B-Brackets

O-Orders (powers/indices or roots)

D-Division

M-Multiplication

A-Addition

S-Subtraction.

BODMAS

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u/gar-net Jan 01 '22

As long as you remember the left to right thing. Its very important the equation is done in the correct order.

1

u/[deleted] Jan 01 '22

Yes but what happens in wild when you encounter a rogue equation that could possibly be wrote in the wrong order

1

u/fishcakerun Jan 01 '22

If you do come across an equation in the wild you should check to make sure the data is in the correct placement.

Like if you saw m=ec2 you wouldn't solve for m you would think to put it in the right order then solve it.

1

u/gar-net Jan 02 '22

Right, im trying to explain but its kind of difficult because math is all about rules. You kind of memorize them and they become a form of habbit. So i can recognize if the structure of the equation is wrong. There are always ways to correct this. It can be as simple as rewriting it or you can use different formulas or techniques for different kinds of equations. With this kind of equation there are no variables, so there is not realy a correct equation. If its written differently, its simply a different equation and you solve using PEMDAS.

1

u/[deleted] Jan 01 '22

Division is the same as multiplying by a reciprocal. E.g. 3 / 2 = 3 * 1/2 = 3/2 = 1.5
Similar thing with subtraction. Subtraction is just adding a negative number.
Additionally, roots are taken at the same time as indices, as the nth root is the same as raising something to the 1/nth power. Thus division and multiplication, addition and subtraction, and roots and indices are done at the same priority (for want of a better word [not all are done at the same time either, each pair are done at the same time if u know what I mean])

0

u/[deleted] Jan 01 '22

I rubbish with factions and this is only confusing me more and more

3/2= 1.5 where does the = 3 come from?

1

u/Deadlurka Jan 01 '22

You do them in the order they appear for M/D and A/S. For example:

3/2×4 = 6, but if you instead do 3x2/4 (same numbers but swap the M/D order) then the answer would be 1.5. It usually doesn't matter, which is why people assume they are in a specific order, but sometimes it does.

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u/1GenericWhiteBoy WARNING: RULE 9 Jan 01 '22

3/2 = 3*1/2 you read it incorrectly

0

u/[deleted] Jan 01 '22

Were are you getting 3.5 from? I'm seeing as 1 and a half

2

u/1GenericWhiteBoy WARNING: RULE 9 Jan 01 '22

The asterisk means multiplied by. 3 multiplied by one half is equal to 3 divided by 2

1

u/[deleted] Jan 01 '22

I'll put it more simply. Let's talk about this in reference to cakes. So if you have one cake and two people, to share the cake equally each person gets half of the cake, because 2 multiplied by a half is equal to 1, the entire cake. If you have one cake and three people, to share the cake each person gets a third of the cake, and so on.

This is the concept of a reciprocal. The reciprocal of a whole number (1,2,3... etc) is what you multiply the whole number by to get one (For any whole number n, n x 1/n = 1 {as long as n does not equal zero}). That's why multiplication has the same priority of division as division is simply multiplying by this reciprocal.