Question

A rectangular swimming pool has a length of $30$ meters, a width of $10$ meters, and an average depth of $2$ meters. If a hose can fill the pool at a rate of $0.5$ cubic meters per minute, how many hours will it take the hose to fill the pool ?

• A. $12$ hrs
• B. $24$ hrs
• C. $20$ hrs
• D. $15$ hrs

Answer 1

Answer: (C)

$20$ hrs

20 hours: The volume of the pool is (length) $\times$ (width) $\times$ (height), or $30\times 10\times 2=600$ cubic meters. Use a standard work equation, RT= W, where W represents the total work of 600 $m^3$.

$0.5\times t=600$

$t=1200$ minutes

Convert this time to hours by dividing by 60: $1200÷60=20$ hours.

Alternatively, you could convert first: $\frac{0.5m^3}{hr}\times 60min=\frac{30m^3}{hr}$

Next, use the standard work equation:

30 t = 600

t = 20 hours