8.Cat question with explanatory answers

Percents - CAT 2011 Sample Questions

Question 1

B as a percentage of A is equal to A as a percentage of (A + B). Find B as a percentage of A.

(A) 62%
(B) 73%
(C) 41%
(D) 57%

Correct Answer is 62% - Choice (A).

Explanation

From the question stem, we know

..... equation I

As B is a percent of A, let us assume B = Ax

Then, equation I can be re-written as

Or x(1 + x) = 1

After this step, trial and error works best. The solution is 62%, answer choice (A) is the correct one.

Alternatively, solving, we get x² + x - 1 = 0

Or x =