Arslan and Bilal have some marbles with them. Arslan told Bilal “if you give me ‘x’ marbles, both of us will have equal number of marbles”. Bilal then told Arslan “if you give me twice as many marbles, I will have 30 more marbles than you would”. Find ‘x’?

A. 4
B. 5
C. 6
D. 8
E. None of these
Explanation:
If Bilal gives ‘x’ marbles to Arslan then Bilal and Arslan would have V – x and A + x marbles.
V – x = A + x — (1)
If Arslan gives 2x marbles to Bilal then Arslan and Bilal would have A – 2x and V + 2x marbles.
V + 2x – (A – 2x) = 30 => V – A + 4x = 30 — (2)
From (1) we have V – A = 2x
Substituting V – A = 2x in (2)
6x = 30 => x = 5.