19-11-2021 Answers

 1. A tap can fill a cistern in 3 hours and another can empty it in 9 hours. If both the taps-> 9/2 hours

2. If a pipe can fill a tank in 4 hours an another pipe can empty the full tank in 5 hours-> 1/12

3. A tank is normally filled in 12 hours. Because of a leak at it's bottom it takes 3 hours more to fill-> 60

4. Two pipes as inlet fill a water tank in 4 hours and 6 hours respectively. One outlet pipe empties the-> 3 hours

5. A tank is normally filled in 8 hours. Because of a leak at it's bottom it takes 4 hours more to fill-> 24

6. A tank is filled in 6 hours by three pipes A, B and C. The pipe C is twice as fast-> 42 hours

7. Pipes A, B and C can fill a tank in 10, 15 and 20 hours respectively. If all three pipes are opened-> 60/13 hours

8. Pipes A, B can fill a tank in 20 and 30 hours respectively. Pipe C can empty the full tank in 25 hours-> 300/13 hours

9. Two taps A and B can fill a cistern in 6 hours and 9 hours respectively. In that beginning-> 1.5 hour(s)

10. A tap can fill a cistern in 3 hours and another can empty it in 6 hours. If both the taps-> 6