Two pipes A and B together can fill a cistern in 4 hours. Had they been opened separately, then B would have taken 6 hours more than A to fill cistern. How much time will be taken by A to fill the cistern separately?
Q1. Two pipes A and B together can fill a cistern in 4 hours. Had they been opened separately, then B would have taken 6 hours more than A to fill cistern. How much time will be taken by A to fill the cistern separately?
Answer: 6 hrs
Explanation: Let A alone take a hours; then B alone takes (a+6) hours; 1/a + 1/(a+6) = 1/4 gives a² − 2a − 24 = 0, so a = 6 hours.