A reservoir is provided by two pipes A and B. A can fill the reservoir 5 hours faster than B. If both together fill the reservoir in 6 hours, the reservoir will be filled by A alone in	Choices:
A) 12 hours  B) 8 hours  C) 10 hours  D) 11 hours  E) None of these
If x is the speed then speed of A= x + 5 and B = x   Time taken by A and B will be x and x + 5 resp.   1/x + 1/x + 5 = 1/6 ; x2 – 7x - 30 = 0 x = -3 or x = 10.   Since time can’t be negative, x =10.   Answer: 10 hours
<result>C</result>
A reservoir is provided by two pipes A and B. A can fill the reservoir 5 hours faster than B. If both together fill the reservoir in 6 hours, the reservoir will be filled by A alone in