Math151 question

Question

One inlet pipe can fill an empty pool in 6 hours, and a drain can empty the pool in 9 hours. How long will it take the pipe to fill the pool if the drain is left open?

Answer 1

fills in 6 hours empties in 9 hours

how long to fill the pool if both are on, draining and filling at the same time

in 18 hours, it fills 3 times and empties 2 times, leaving it filled once

It takes 18 hours to fil the pool l with the drain open

6x3 = 9x2 = 18