A pump can fill a tank with water in 3 hours. Because of a leak, it took 6 hours to fill the tank. The leak can drain all the water in ?
Choose the correct answer:
A) 2hr
B) 1hr
C) 3hr
D) 4hr
E) 6hr
Work done by the leak in 1 hour = 1/3 - 1/6 = 1/6   Leak will empty the tank in 6 hours   Answer is 6hr
<result>E</result>
A pump can fill a tank with water in 3 hours. Because of a leak, it took 6 hours to fill the tank. The leak can drain all the water in ?