Hello,Originally Posted by pochoa
I'm very sorry, but your answer couldn't be right because one hose needs a lot more time to fill the swimmingpool than both hoses together.
Let's have another try:
(I use SP as abbreviation for "swimmingpool")
Bob's hose needs b hours to fill the SP.
Jim's hose needs j hours to fill the SP.
Bob's hose delivers per hour.
Jim's hose delivers per hour.
Both hoses together delivers per hour.
They need 18 hours to fill the SP:
Divide both sides of the equation by SP and you get:
As we know that we can substitute b by j:
I leave the next steps to you.
As the final result you'll get b=32.4 hrs (32 h; 24 min) and j = 40.5 hrs (40 h; 30 min).