Level 3
Mr Gopi uses two pipes to fill a pool. The first pipe can fill the pool in 6 h. The second pipe can fill the pool in 8 h. Two house after both pipes are turned on, Mr Thomas accidentally opens the pipe which can drain the pool completely in 12 h. With the 3rd pipe now remained open, what is the total time taken by Mr Gopi to fill the pool completely? Express your answer in h.
4 m
Level 2
A rectangular tank measuring in 40 cm by 15 cm by 20 cm is 25 filled with water. How much water is needed to fill the tank to 50% of the capacity? Give your answer in litres.
3 m
Level 3
At 10 a.m., Mrs Leng used two taps to fill up a tank. Tap A could fill the tank in 4 h. Tap B could fill the tank in 3 h. 1 hour after both taps were turned on, Tap B was faulty and stopped working. Mrs Leng accidentally opened Tap C which could drain a full tank completely in 2 h. Instead of being filled, the tank was emptied. How long did it take for the tank to be completely empty? Express your answer in mixed number.
4 m
Level 3
An open tank of depth 20 cm has a horizontal base of length 40 cm and breadth 25 cm. Two wooden cubes, of side 8 cm and 10 cm respectively, rest on the base of the tank.
  1. Find the capacity of the tank.
  2. How much water must be poured into the tank so that the tank is half filled?
3 m
Level 3
A tank with a base measuring 60 cm by 10 cm had two leaks at 400 cm3 per minute and 300 cm3 per minute respectively. If the water level was 15 cm originally, what would be the height of water in the tank after 6 minutes?
4 m