Ratios

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Ratios

by jayanti » Mon Aug 08, 2011 1:14 am
For each $2 spent by the nation's Defense Department, the Energy Department spends $0.40. For every $8 spent by the Energy Department, the Social Services Department spends $3. The ratio of the money spent by the Defense Department to the money spent by the Energy Department to the money spent by the Social Services Department can be expressed as:

A) 40:8:3

B) 20:4:1

C) 8:4:1

D) 4:1:5

E) 2:1:5

correct answer is A
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by Touseef » Mon Aug 08, 2011 1:18 am
Hi Jayanti,

D:E=2:0.4--->Ratio(1)

E:S=8:3---->Ratio(2)

What is D:E:S?

Multiply Ratio(1) by 20,it becomes

D:E=40:8

Hence,D:E:S=40:8:3

The Logic is,We have E common in both ratios.Hence,we have to make the value of E in both these ratios same so that a relationship can be established between D,E and S.

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by jayanti » Mon Aug 08, 2011 5:03 am
Hi Touseef, thanks a lot.... I missed that point. :)

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by GmatKiss » Mon Aug 08, 2011 6:18 am
Given,

D:E=5:1 -a
E:S=8:3 -b

To find, D:S:E
from a and b, we have E common, make it equal in 1 and 2.

D:E=40:8
E:S=8:3

so D:S:E = 40:8:3 (A)