Question

The volume of a cylinder varies jointly with the square of its radius and with its height: V=kr^(2)h Cylinder A has a volume of 251.2 cubic inches and has a radius of 4 inches and a height of 5 inches. What is the volume of cylinder B, which has a radius of 3 inches and a height of 9 inches?

Answer 1

We have the following equation:
 V = kr ^ (2) h
 For cylinder A we have:
 251.2 = k * ((4) ^ (2)) * (5)
 Let's clear k:
 k = 251.2 / (((4) ^ (2)) * (5))
 k = 3.14
 For cylinder B we have:
 V = 3.14 * ((3) ^ (2)) * (9)
 V = 254.34 in ^ 3
 Answer:
 the volume of cylinder B is:
 V = 254.34 in ^ 3