The ratii of two cylinder area in the ratio `2 : 3` and their heights are in the ratio `5 : 3`. The ratio of their curved surface area is

Options

A. `2 : 5`
B. `8 : 7`
C. `10 : 9`
D. `16 : 9`

Answer

C

Explanation

Let `(R_(1))/(R_(2)) = (2)/(3) and (H_(1))/(H_(2)) = (5)/(3)`
Required ratio `= (2pi R_(1) H_(1))/(2pi R_(2)H_(2)) = ((R_(1))/(R_(2))) xx ((H_(1))/(H_(2))) = ((2)/(3) xx (5)/(3)) = (10)/(9) = 10 : 9`