Question

You are filling a cylindrical drum (D = 22.5 in., H = 33.5 in.) with water flowing from a garden faucet at a rate of 10 GPM. How long will you have to wait to fill the drum? Express you answer in minutes.

Answer 1

First, remember that 1 GPM (1 gallon per minute) is 231 in³/min.

Find the volume:

$$V=AH=\frac{\pi D^2}4H=13320\text{ in}^3.$$

The time:

$$t=\frac Vq=\frac{13320}{10·231}=5.77\text{ min}.$$