Question

A tank can be filled by one tap in 2 hrs. and by another in 3 hrs. How long will it take if both taps are opened together ?

• A. 6/5 hrs.
• B. 5/6hrs.
• C. 1/5 hrs
• D. 2.5 hrs

Answer 1

Answer:

A. 6/5 hrs.

Time taken to fill the tank with the first pipe = 2hr Time taken to fill the tank with the second pipe = 3hr The work done by the first pipe in one hour = 1/2 The work done by the second pipe in one hour= 1/3 The work done by both pipes together in one hour= 1/2 + 1/3 = 5/6 If both pipes are opened together, the time taken to fill= 1/(5/6) = 6/5hr