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48÷2(9+3)=?


Casper

48÷2(9+3)=?  

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  1. 1. 48÷2(9+3)=?

    • 2
      82
    • 288
      88


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A man walks to the edge of a cliff near a large body of water and says "see/sea", which one does he mean?

Typical liberal dumbass doesn't know how to solve the problem so they make up something else to talk about. My question had the number two in it which is part of both possible answers to the original question therefore relevant to the discussion. Yours was about Obama care or some such shit.

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1. So, distributive properties of mathematics no longer apply.

2. Fractional properties no longer exist.

3. Calculators rule, they are never wrong.

4. People can't calculate with pencil and paper (that analog thing).

We're in deep doodoo...

edit: 5. oh and no one knows how to write a proof to determine if a solution is correct. An engineering fundamental from day one.

edit2: And spacecraft do fall out of the sky. The last decent one was a Mars lander that somebody got confused about whether they were looking at SAE or metric values, in calculating orbital parameters. It pretty much hit the ground before it's parachute opened. Just like in a cartoon.

Edited by ReconRat
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1. So, distributive properties of mathematics no longer apply.

2. Fractional properties no longer exist.

3. Calculators rule, they are never wrong.

4. People can't calculate with pencil and paper (that analog thing).

We're in deep doodoo...

Exactly!

Oh and Uncle Punks Obama comment to JRMMiii was hilarious! :lol:

Also, I'm burnt out on this thread so I'm not longer arguing it. Put that in your pipe and smoke it. :D

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I thought this seemed like a pretty complete answer but even the author seems to agree the equation is poorly stated as is.

The Distributive Property is just a PROPERTY (hence the name) and it ONLY states that 2(9+3) is the SAME as (2*9) + (2*3). It DOES NOT imply or govern WHEN or even IF this operation must occur, that fact is governed by the order of operations.

The problem with your "solving" of the equation above is that you misapply the distributive property when you multiplied the "x" into the parenthetical expression: your (x*9 + x*3) part

Instead, you must reduce the parentheses FIRST to get: 48/x(12) = 2

Now solve for x by dividing both sides by 12 (or 48 if you choose):

48/x = 2/12

invert both sides:

x/48 = 12/2

multiply both sides by 48:

x=48(12/2)

x=288

The gist of this debate really centers on whether you interpret the "/" to mean just the 2 is in the demoninator like this:

48

---- * (9+3)

2

or if the entire remainder of the expression is in the denominator like this:

48

-----------

2(9+3)

It's generally accepted that the first interpretation is the correct one.

@David - how did I butcher the equation?

And I understand the Dist. Property fine...it simply just doesn't come into play here. As I said the first decision is how you view the divide by sign, if you think everything to the right is in it's denominator, then you simply reduce the term in the parentheses to 12 and solve a simple equation for x:

48

-------- = 2

x(12)

multiply both sides by x, x's on left cancel:

48

---- = 2x ---> 4 = 2x ----> x = 2

12

on the other hand if you think the divide by sign only applies to the x, you likewise simplify the parentheses and solve for x. YOU DO NOT NEED TO DISTRIBUTE:

48

-- * (9+3) = 2

x

48

----- * 12 = 2 ----> 576/x = 2

x

multiple both sides by x, x's on left cancel:

576 = 2x -----> x = 288

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ok so i talked to one of the top engineers at goodyear, he even said its 2. he said he understands how people get it wrong because they dont know pemdas. i guess this thread shows who payed attention in class and who didnt. "my teachers taught me wrong if thats the case" no you just didnt listen.

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ok so i talked to one of the top engineers at goodyear, he even said its 2. he said he understands how people get it wrong because they dont know pemdas. i guess this thread shows who payed attention in class and who didnt. "my teachers taught me wrong if thats the case" no you just didnt listen.

i forgot you know all my bad, its clearly because I never listened....:bow:

Edited by Bad324
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ok so i talked to one of the top engineers at goodyear, he even said its 2. he said he understands how people get it wrong because they dont know pemdas. i guess this thread shows who payed attention in class and who didnt. "my teachers taught me wrong if thats the case" no you just didnt listen.

Note to self ... do not buy Goodyear ...

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scottie - stfu, this has nothing to do with PEMDAS.....mult and div have the same rank, its left to right. nobody else is even talking about that shit....your top engineer is a retard too if he believes that.

A common technique for remembering the order of operations is the abbreviation "PEMDAS", which is turned into the phrase "Please Excuse My Dear Aunt Sally". It stands for "Parentheses, Exponents, Multiplication and Division, and Addition and Subtraction". This tells you the ranks of the operations: Parentheses outrank exponents, which outrank multiplication and division (but multiplication and division are at the same rank), and these two outrank addition and subtraction (which are together on the bottom rank). When you have a bunch of operations of the same rank, you just operate from left to right.

http://www.purplemath.com/modules/orderops.htm

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ok so i talked to one of the top engineers at goodyear, he even said its 2. he said he understands how people get it wrong because they dont know pemdas. i guess this thread shows who payed attention in class and who didnt. "my teachers taught me wrong if thats the case" no you just didnt listen.

:nono:

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A Google quote isn't much better than a Wiki quote. And that batch of math in #249 has taken some serious liberties to get the results desired. Math (numbers) can do anything you want. That doesn't make it right.

Again, honestly, I used to get textbooks for free to review, in hopes that we would buy them from the publisher for classes/students. They were full of mistakes. Horrible mistakes, in many cases. That made me wonder just who the hell wrote them. Just don't automatically believe everything you see and hear and read. Challenge everything, and make your own decisions.

edit: Darwin will take care of the rest :D

Edited by ReconRat
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