If a and b are both positive, what percent of b is a?

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by GMATGuruNY » Tue Mar 27, 2018 4:30 am
VJesus12 wrote:If a and b are both positive, what percent of b is a?

(1) a = 3/11
(2) b/a = 20
Question: What FRACTION of b is a?
In other words: a is what FRACTION of b?
Answer: a/b.
Question: What PERCENT of b is a?
In other words: a is what PERCENT of b?
Answer: a/b * 100.
To convert the fraction in blue to a percent, we simply multiply by 100.

Thus, to answer the question stem above, we need to know the value of a/b.
Question stem, rephrased:
What is the value of a/b?

Statement 1:
No information about b.
INSUFFICIENT.

Statement 2:
b/a= 20/1
a/b = 1/20.
SUFFICIENT.

The correct answer is B.
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