A tank has two inlet pipes, A and B, which can fill the tank in 12 hours and 18 hours respectively, and an outlet C which can empty the tank in 9 hour

B) Pyramid of energy

C) both ‘A’ and ‘B’

Correct option is (D) \(7\,\frac{1}{2}\) hrs \(\because\) Time taken to fill a \(50\,l\) of tank = 5 hours \(\therefore\) Time taken to fill a \(75\,l\) of tank \(=\frac5{50}\times75\;hours\) \(=\frac{75}{10}\;hours\) = 7.5 hours = 7 hours + \(\frac12\) hours = \(7\frac12\) hours

Correct option is (C) 96 Time = 1 hr 20 minutes = (60+20) minutes = 80 minutes Total work done by 6 pumps in 1 hr 20 minutes \(=6\times80=480.\) Let 5 pumps take time to fill the...

Correct option is (B) 36 Total work done by 24 men in 14 days by working 6 hours a day \(=24\times14\times6\) Let x men are required to complete same work in 8 days...

Correct Answer - C Consider, the filling of tank as a positive work and emptying the tank as negative work.

Correct Answer - 18