The surface areas of two similar shapes are proportional to
the squares of their corresponding sides
S(Cylinder 1)/S(cylinder 2) = 4^2/1^2 = 16
So A's surface area is 16 times that of B's surface
or, the long way ...
cylinder B: radius -- r, height --- h
cylinder A: radius = 4r, height = 4h
surface area of A = 2πr^2 + 2πrh = 2(πr^2 + πrh)
surface area of B = 2π(16r^2) + 2π(4r)(4h)
= 32πr^2 + 32πrh = 32(πr^2 + πrh) or 16 times that of A
Cylinder A has radius 4 times the radius of cylinder B, and height 4 times the height of cylinder B.
What is the ratio of the lateral area of A to the lateral area of B?
1 answer
1 answer