A tank is filled in 4 hours by three pipes A, B and C. The pipe C is twice as fast as B and pipe B is thrice as fast as A. How much time will pipe A alone take to fill the tank?
Answer & explanation
Correct answer: option 2
A + B + C = 4 hrs,
The pipe C is twice as fast as B and pipe B is thrice as fast as A. therefore,
A : B : C = 1 : 3 : 6 (Efficiency)
⇒ Total capacity = (1 + 3 + 6) x 4 = 10 x 4 = 40 hrs,
⇒ Time required by A to completely fill the cistern alone = \(\frac{40}{1}\) = 40 hours.