Pipes and Cistern

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 the cistern. How much time will be taken by A to fill the cistern separately?

A 1 hours

B 2 hours

C 6 hours

D 8 hours

ANS:C - 6 hours

Let the cistern be filled by pipe A alone in x hours. Then, pipe B will fill it in (x + 6) hours.

1 + 1 = 1
x (x + 6) 4
x + 6 + x = 1
x(x + 6) 4
x2 - 2x - 24 = 0 (x -6)(x + 4) = 0 x = 6.     [neglecting the negative value of x]



img not found
img

For help Students Orientation
Mcqs Questions

One stop destination for examination, preparation, recruitment, and more. Specially designed online test to solve all your preparation worries. Go wherever you want to and practice whenever you want, using the online test platform.