Problema Solution

two pipes running simultaneously can fill a swimming pool in 6 hours. if both pipes run for 3 hours and one pipe is shut off, it takes 4 hours more for the remaining pipe to fill the pool. how long would it take for each pipe running separately to fill the pool?

Answer provided by our tutors

let


x = the time the first pipe needs to fill the swimming pool alone

y = the time the second pipe needs to fill the swimming pool alone


if the both pipes run 1 hour they will fill 1/6 of the pool


1/x + 1/y = 1/6


if the both pipes run for 3 hours and one is shut off it needs 4 hours more for the remaining pipe to fill the pool


3/x + 3/y + 4/y = 1


by solving the system of equations


1/x + 1/y = 1/6

3/x + 3/y + 4/y = 1


the positive solution


x = 24 hours

y = 8 hours


the first pipe alone needs 24 hours to fill the pool.

the second pipe alone needs 8 hours to fill the pool.