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When two hoses are connected to a swimming pool, they can fill the pool in 4 hrs if both are open.
If only the larger hose is open, it can fill the pool in 6 hrs less than the smaller hose.
How long will it take each hose to fill the pool?
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Let x = hours to fill, for the smaller hose.
Then the time for the larger hose to fill the pool is (x+4) hours.
The equation for the combined rate of work is.
+ = . (1)
To solve it, multiply both sides by 4. You will get
+ = 1. (2)
From this point, I just see the answer. It is x= 6 hours.
CHECK equation (2). Its left side is + = + = 1 ! Correct !
Alternatively, you can reduce equation (2) to a quadratic equation
and solve it using the quadratic fotmula or factoring.
Knowing the answer will facilitate your job.
Solved and explained.