DS - Coats Q.

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DS - Coats Q.

by mrkylee » Fri Dec 21, 2007 7:09 pm
a store purchased 20 coats that each cost an equal amount and then sold each of the 20 coats at an equal price. what was the store's gross profits on the 20 coats?

1. if the selling price per coat had been twice as much, the store's gross profit on the 20 coats would have benn $2,400.

2. if the selling price per coat had been $2 more, the store's gross profit on the 20 coats would have been $440.

Thanks....
Source: — Problem Solving |

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by sujaysolanki » Fri Dec 21, 2007 10:42 pm
From stem SP of 20 = CP of 20


From 1 say cp = x sp = 2x p can be found Hence sufficient

From 2 also we have a relationship in terms of x Hence sufficient

Hence D

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DS - Coats Q

by ray » Sun Dec 23, 2007 12:36 pm
It can't be "D". Here's why:

First let deduce an equation from the word problem:
X = selling price
Y = purchase price
Z = Profit

Therefore: 20X – 20Y = Z --- Let's call it Equation 1

Are goal here is to find Z. Now let's look at statements 1 and 2 individually.

1.

20(2X) – 20Y = 2400
40X – 20Y = 2400
2X – Y = 2400 --- Let's call it Equation 2

We can’t solve this further because we have 3 variables in Equation 1 and we need 3 distinct equations to solve this further.

Now lets look at statement 2

2. From the statement we can deduce the following equation:
20(X+2) – 20Y = 440
20X + 40 – 20Y = 440
X + 2 – Y = 22
X – Y = 20 --- Let's call it Equation 3

We are faced with a similar situation as we had encountered in statement 1. But wait, we don't need another distinct equation. If we multiply Equation 3 by “20” we get:

20X – 20Y = 400

AH! We only need statement 2 to answer this question. Therefore, the answer is “B”.

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by sujaysolanki » Sun Dec 23, 2007 8:42 pm
Thanks for the correction ..it shd be B