Question

The radii of two cylinders 3:2 and height 7:4.find the ratios of their curved surface area.

Answer 1

a = 2pi*r*h
a' = 2pi(2/3 r)(4/7 h) = 2pi*rh*8/21

a:a' = 1:8/21 = 21:8

Note that the ratio is just the product of the linear ratios.

Answer 2

Thank you