An inlet pipe on a swimming pool can be used to fill the pool in 47 hours. The drain pipe can be used 5o empty the pool in 48 hours. If the pool is 1/2 filled and then the inlet pipe and drain pipe are opened, how long from that time will it take to fill the pool?

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.