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OG 13 181

by oquiella » Tue Dec 22, 2015 3:18 pm
If M>0 and x is m percent of y, then, in terms of M, y is what percent of x.

A. 100m
B. 1/100m
C. 1/m
D. 10/m
E. 10,000/m


Answer: E


Please eexplain reasoning
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by MartyMurray » Tue Dec 22, 2015 9:11 pm
If m > 0 and x is m percent of y, then, in terms of m, y is what percent of x?

A. 100m
B. 1/100m
C. 1/m
D. 10/m
E. 10,000/m
If x is m percent of y, then x = (m/100) * y

x = ym/100

100x = ym

100x/m = y

x = 100% of x

So y = (100 * 100% of x)/m --> y = (10,000% of x)/m

The correct answer is E.
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by [email protected] » Wed Dec 23, 2015 9:12 am
Hi oquiella,

This question can be solved by TESTing VALUES.

We're told that M > 0 and X = M% of Y. We're asked Y is what percent of X.

IF...
M = 50
Y = 20
X = 10

20 is 200% of 10. So we're looking for an answer that equals 200 when M = 50. There's only one answer that matches...

Final Answer: E

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by oquiella » Tue Dec 29, 2015 5:58 am
Marty Murray wrote:
If m > 0 and x is m percent of y, then, in terms of m, y is what percent of x?

A. 100m
B. 1/100m
C. 1/m
D. 10/m
E. 10,000/m
If x is m percent of y, then x = (m/100) * y

x = ym/100

100x = ym

100x/m = y

x = 100% of x

So y = (100 * 100% of x)/m --> y = (10,000% of x)/m

The correct answer is E.
Where did x= 100% of x come from?

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by regor60 » Tue Dec 29, 2015 6:47 am
oquiella wrote:
Where did x= 100% of x come from?
100% = 100/100 or 1.

"100% of X" is the same thing as 100% times X.

So, 1 times X = X is always true