Question

A cylinder has a radius of 4 inches and a height of 5 inches. Which of these dimensions of a cylinder will have the same volume?

Radius: 20 inches
Height: 60 inches


Radius: 2 inches
Height: 20 inches


Radius: 10 inches
Height: 8 inches


Radius: 8 inches
Height: 5 inches

Answer 1

Radius: 2 inches

Height: 20 inches

Explanation:

Use the formula V = πr2h to solve the problem.

Answer 2

Radius: 2 inches

Height: 20 inches

Explanation:

`R=4\,,\ H=5\ \implies \ \ V=\pi R^2\cdot H=\pi\cdot 4^2\cdot5=80\pi\\\\\\R=20\,,\ H=60\ \implies \ \ V=\pi\cdot20^2\cdot60=24000\pi\\e80\pi\\\\R=2\,,\ H=20\ \implies \ \ V=\pi\cdot2^2\cdot20=80\pi \\\\R=10\,,\ H=8\ \implies \ \ V=\pi\cdot10^2\cdot8=800\pi\\e80\pi\\\\R=8\,,\ H=5\ \implies \ \ V=\pi\cdot8^2\cdot5=320\pi\\e80\pi`