A tank can be filled by one tap in 20 min and by another in 25 min Both the taps are kept open for 5...........

Quantitative Aptitude ( CCS) Pipes&cistern

A tank can be filled by one tap in 20 min. and by another in 25 min. Both the taps are kept open for 5 min. and then the second is turned off. In how many minutes more is the tank completely filled ?

17½ min

12 min

11 min

6 min

छोटे Courses बड़े Results

Master Pipes&cistern

Prepare through Micro-courses

Try Now

Explanation:

Work done by both in 5 minute = (1/20 + 1/25) = 9/20
Remaining part = (1 - 9/20) = 11/20
Now, 1/20 part is filled in 1 minute. So, 11/20 part will be filled in 11 minute.
Hence, the tank will be full in 11 min more.