Problema Solution
Working together, two pumps can drain a certain pool in 6 hours. If it takes the older pump 15 hours to drain the pool by itself, how long will it take the newer pump to drain the pool on its own?
Answer provided by our tutors
it takes the older pump 15 hours to drain the pool by itself thus the rate of the old pump is 1/15 pools per hour
working together, two pumps can drain a certain pool in 6 hours thus the together rate is 1/6 pools per hour
let x = the hours the newer pump needs to drain the pool alone. its rate is 1/x pools per hour
1/x + 1/15 = 1/6
by solving we find
x = 10 hr
click here to see the step by step solution of the equation
the newer pump will need 10 hours to drain the pool on its own.