RRB Technician (Grade I Signal + Grade III) 2018 · Question 158 of 213

Pipes A, B and C are attached to an empty cistern. While the first two can fill the cistern in 4 and 10 hours,respectively, the third can drain the cistern, when filled, in 6 hours. If all the three pipes are opened simultaneously when the cistern is three-fifth full, how many hours will be needed to fill the cistern?

best-effort

1. A$$\frac{36}{11}$$
2. B$$\frac{48}{11}$$
3. C$$\frac{60}{11}$$
4. D$$\frac{24}{11}$$Correct