A pipe can fill a tank in 56 hours, but it takes 16 hours more due to a leak in its bottom. In how much time (in hours) can the leak alone empty $83\frac{1}{3}$% of the tank?
Answer & explanation
Correct answer: option 2
A+ = 56 hrs, A + B = 72 hrs,
⇒ A + B = 7 (Efficiency)
⇒ 9 + B = 7,
⇒ B = -2,
Time required for B to empty 83.33% of tank = 83.33% x 504 = 420 units,
⇒ \(\frac{420}{2}\) = 210 hrs.