Question

Two pipes are used in filling a swimming pool-first is the large pipe,while the second is the small pipe.Both pipes can fill the pool in 3hours,but if only the large pipe is used,the pool is filled in 5hours.How long will take to fill the pool using only the small pipe?(show solution)​

Answer 1

Answer:

7 hr 30 min

Step-by-step explanation:

Both Pipe can fill the pool in 3 hours.

(i. e 1/3 rd of work is done in 1 hr)

Large pipe alone can fill the pool in 5 hours

Small pipe alone can fill a pool in x hours

$\frac{1}{x} + \frac{1}{5} = \frac{1}{3}$

$\frac{1}{x} = \frac{2}{15}$

Small pipe alone can fill a pool in 15/2 hours or 7.5 hours or 7 hour 30 min