SOLUTION: Ok, so i have done this problem twice (two different ways) and i have gotten two different answers in doing so. Here is the word problem: Five times a number decreased by 18

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Question 773210: Ok, so i have done this problem twice (two different ways) and i have gotten two different answers in doing so.
Here is the word problem:
Five times a number decreased by 18 minus 4 times the same number is -36.
I tried: 5x-(18-4x)=-36 and got x=-2
But ive also tried: 5x-18-4x=-36 and got x=-18.
So as you can see I'm confused on which way is the correct way.

Found 2 solutions by Edwin McCravy, josgarithmetic:
Answer by Edwin McCravy(20056)   (Show Source): You can put this solution on YOUR website!
Ok, so i have done this problem twice (two different ways) and i have gotten two different answers in doing so.
Here is the word problem:
Five times a number decreased by 18 minus 4 times the same number is -36.
I tried: 5x-(18-4x)=-36 and got x=-2
But ive also tried: 5x-18-4x=-36 and got x=-18.
So as you can see I'm confused on which way is the correct way.
-------------------------------------

This is a classic example of a poorly written word problem.  
It is very ambiguous.

It could also be interpreted this way:

5(x - 18) - 4x = -36

That gives the answer 54.  There are a number of other ways it 
could be taken, depending on how you group the words.

You are right to complain about this problem!  It is really ambiguous 
as you discovered.


1. (Five times a number) decreased by (18 minus 4 times the same number) is -36.

2. Five times (a number decreased by 18) minus (4 times the same number) is -36.

3. Five times [a number decreased by (18 minus 4)] times the same number is -36.

4. (Five times a number) decreased by (18 minus 4) times the same number is -36.

and bunches more ways.

Edwin

Answer by josgarithmetic(39618)   (Show Source): You can put this solution on YOUR website!
Your description is ambiguous.

Trying phrase by phrase,
Five times a number----------------- .
Decreased by 18--------------------- .
Minus 4 times the same number-------- .
Is -36 -------------------------------

Trying to guess at the phrasing meanings,
Five times a number-----------
Decreased by 18 minus 4 times same number--------
Is -36 --------------------------------------

Those two equations are not equivalent. Their solutions are not the same. The problem description needs to be more precise in order to tell which form is the one expected.

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