Question

A swimming pool is to be drained. The pool is shaped like a rectangular prism with length 28 ft, width 14 ft, and depth 5 ft. Suppose water is pumped out of the

pool at a rate of 140 ft per hour. If the pool starts completely full, how many hours does it take to empty the pool?

Answer 1

We need volume

`\\ \tt\hookrightarrow LBH`

• L=length
• B=width
• H=height

`\\ \tt\hookrightarrow V=28(14)(5)`

`\\ \tt\hookrightarrow V=1960ft^3`

• Rate of output=140ft

Total time

`\\ \tt\hookrightarrow (1960)/(140)=14h`

Answer 2

• 14 hours

Explanation:

We know that:

• L = 28 ft.
• W = 14 ft.
• D = 5 ft.
• 140 ft. = 1h

Solution:

• Volume of pool: 28 x 14 x 5
• => Volume of pool: 14 x 14 x 5 x 2
• => Volume of pool: 196 x 10
• => Volume of pool: 1960 ft³
• => Time to empty the pool: 1960/140
• => Time to empty the pool: 14 hours

Hence, it takes 14 hours to empty the pool.