A sphere and a cube have equal surface areas. The ratio of the volume of the sphere to that of the cube is
(I) ãƒÎ : ã6
(2) 2 : ã ƒÎ
(3) 㠃Π: 3
(4) ã 6 : ã ƒÎ
The ages of two persons differ by 20 years. If 5 years ago, the elder one be 5 times as old as the younger one, their present ages (in years) are respectively:
1) 30, 10
2) 25, 5
3) 29, 9
4) 50, 30
