For any positive x, y and k, if kx is n% of y, then what percentage must x be of y?
A. (n/k)%
B. (n + k)%
C. (nk)%
D. (n – k)%
E. (100 × n/k)%

(A) The statement kx is n% of y means that:
kx = [n / 100] × y
x = y × (n / k / 100)

Therefore x is (n / k)% of y. The correct answer is choice (A).
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Hi, there is some ambiguity in your answers. In Math3 Test Q. no. 24, I chose option (A), but you gave answer as (E). Here in Math4 Test Q.no.27 is similar to that question, but here you have given answer as (A), though I chose answer (E). Can you explain this?

These are two similar but DIFFERENT questions. The have different answers. There is no ambiguity in that. Different questions have different answers.

The similar question: http://800score.com/forum/viewtopic.php?f=3&t=5019

Now let's discuss the things these questions have in common.
1. They deal with percentages.
2. No specific integers are given, just variables.

We use the same plan in both questions.
1. Transform wording into algebra.
The statement kx is n% of y means that:
kx = [n / 100] × y

2. Transform the original formula into x = (P / 100) × y, which the same as wording x is P% of y.
x = [(n/k) / 100] × y

P% is the answer.
A. (n/k)%