The radii of two cones are in ratio 2:1, their volumes are equal. Find the ratio of their heights.	Choose the correct choice from the following answers:
A) 1 : 4
B) 1 : 3
C) 1 : 2
D) 1 : 5
E) none of these

Rationale: explanation : let their radii be 2 x , x and their heights be h and h resp . then , volume of cone = 1 / 3 π r 2 h 1 / 3 ∗ π ∗ ( 2 x ) 2 ∗ h / 1 / 3 ∗ π ∗ x 2 ∗ h = > hh = 14 = > h : h = 1 : 4 option a
Answer: A