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.