If the volume of two cubes are in the ratio 8:1, the ratio of their edges is:	Choose the correct choice from the following.
A) 2 : 1	B) 3 : 2	C) 3 : 5	D) 3 : 7	E) none of these

Rationale: explanation : let the edges be a and b of two cubes , then a 3 / b 3 = 8 / 1 = > ( a / b ) 3 = ( 2 / 1 ) 3 a / b = 2 / 1 = > a : b = 2 : 1 option a
Answer: A