How Long will It Take to Either Completely Filled or Emptied as the Case may be?

A tap can fill a tank kin 16 min and another can empty it in 8 min. If the tank is already ½ filled and both the taps are opened together. Will the tank be filled or emptied? How long will it take to either completely filled or emptied as the case may be?

  1. Emptied in 16 min
  2. Filled in 8 min
  3. Emptied in 8 min
  4. Filled in 12 min
Anurag Mishra Professor Asked on 28th November 2015 in Maths.
Add Comment
1 Answer(s)

Answer: (3) Emptied in 8 min

A tap can fill a tank = 16 min
Therefore, A tap can fill in a min = 1/16

B tap can fill a tank = 8 min
Therefore, B tap can fill a min = 1/8

A and B can empty a tank in a min = 1/8 – 1/16
= (2 – 1)/16
= 1/16

Therefore, A and B can empty a tank = 16 min

If the tank is all ready 1/2 filled.
Then, half tank will be empty = (1/16) 1/2
= 1/8

So, the tank emptied in 8 min.

Hence, the answer is (3) Emptied in 8 min.

Anurag Mishra Professor Answered on 29th November 2015.
Add Comment

Your Answer

By posting your answer, you agree to the privacy policy and terms of service.