Eight taps are fitted in a tank, some are inlet taps and rest is outlet taps. Each inlet tap can fill the tank in 12 hours and each outlet tap can empty it in 36 hours. Find the number of inlet taps, if the whole tank filled in 3 hours.

05

                  Inlet(+)   :   Outlet(-)

Time        :     12       :      36   

Efficiency:       3        :       1

Total work  = efficiency x time = 1 x 36 = 36 ltr

Let no. of inlet taps be n, no. of outlet taps = 8 - n

ATQ,

⇒ [3n - (8 - n) x 1] x 3 = 36

⇒ 4n - 8 = 12

⇒ n = 5

No. of inlet pipes = 5