Question

18 pumps can empty a water tank in 12 hours .In how many hours can 27 such pumps empty the same water tank

Answer 1

Dear student,
$$\begin{gathered} Timetakenby18pumpstoempty\tan k=12hrs \\ Timetakenby1pumpstoempty\tan k=12\times 18hrs \\ Timetakenby27pumpstoempty\tan k=\frac{12\times 18}{27}hrs \\ =\frac{12\times 2}{3} \\ =\frac{4\times 2}{1} \\ =8hrs \end{gathered}$$
Regards