Pipe A can fill an empty tank in 30 hours and B can fill it in 10 hours. Due to a leakage in the tank, it takes pipes A and B together 1.5 hours more to fill it completely that it would have otherwise taken. What is the time taken by the leakage alone to empty the same tank completely, starting when the tank is completely full?
Answer & explanation
Correct answer: option 4
A+ = 30 hrs, B + = 10 hrs,

⇒ A + B + C would've taken 1.5 hr more than A + B to fill the tank, therefore,

⇒ A + B + C = 10, (Efficiency)
⇒ 3 + 9 + C = 10,
⇒ 12 + C = 10,
⇒ C = -2,
⇒ Time required for C to empty the tank alone = \(\frac{90}{2}\) = 45 hours.