Multiple choice

A sphere and a cylinder have equal radii of their bases as 7 cm. If their curved surface areas are in the ratio 2 : 7, then find the ratio of radius and height of the cylinder.

  1. 1 : 7

  2. 1 : 3

  3. 2 : 3

  4. 3 : 4

  5. None of these

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Curved surface area of sphere/Curved surface area of cylinder = 2/7

4πr2/2πrh = 2/7

2r/h = 2/7

h = 49

Now, the ratio of radius and height of the cylinder = 7/49 = 1 : 7