Having the same capacity 9 taps fill up a water tank in 20 minutes. How many taps of the same capacity are required to fill up the same water tank in 15 minutes ?

Solution (By Examveda Team)

$$\eqalign{ & \left[ {\frac{{{m_1} \times {h_1} \times {t_1}}}{{{w_1}}} = \frac{{{m_2} \times {h_2} \times {t_2}}}{{{w_2}}}} \right] \cr & {9_{taps}} \times {20_{\min }} = {t_{taps}} \times {15_{\min }} \cr & t = 12\,\,{\text{taps}} \cr} $$