Answer:
10.5 hours.
Step-by-step explanation:
Given,
Two pumps can drain a certain pool in 6 hours.
So, the combined one hour work of the pumps = [tex]\frac{1}{6}[/tex],
Also,older pump takes 14 hours to drain the pool by itself,
The one hour work of older pump = [tex]\frac{1}{14}[/tex],
Thus, the one hour work of newer pump = Combined one hour work - one hour work of older pump,
[tex]=\frac{1}{6}-\frac{1}{14}[/tex]
[tex]=\frac{7-3}{42}[/tex]
[tex]=\frac{4}{42}[/tex]
Hence, the total time taken by newer pump = [tex]\frac{1}{4/42}=\frac{42}{4}=10.5\text{ hours}[/tex]
