SOLUTION: an in-ground pool can be filled in 12 hours if water enters through a pipe alone, or in 30 hours if water enters through a hose alone. if water is entering through both the pipe an

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Question 381380: an in-ground pool can be filled in 12 hours if water enters through a pipe alone, or in 30 hours if water enters through a hose alone. if water is entering through both the pipe and the hose, how long will it take to fill the pool?
PLEAASE HELP MEE!!
Found 2 solutions by neatmath, stanbon:
Answer by neatmath(302) About Me  (Show Source):
You can put this solution on YOUR website!

The easiest way to set up these types of problems:

1%2Fpipe%2B1%2Fhose=1%2Fx

1%2F12%2B1%2F30=1%2Fx

30%2F360%2B12%2F360=1%2Fx

42%2F360=1%2Fx

42x=360

x=360%2F42

x=60%2F7

It will take approximately 60/7 hours to fill the pool using both the hose and the pipe.

This is about 8.57 hours, which makes numerical sense, since it will obviously be faster to fill the pool using both methods rather than one method alone.

I hope this helps!

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
an in-ground pool can be filled in 12 hours if water enters through a pipe alone, or in 30 hours if water enters through a hose alone. if water is entering through both the pipe and the hose, how long will it take to fill the pool?
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pipe rate = 1/12 job/hr
hose rate = 1/30 job/hr
Together rate = 1/x job/hr
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Equation:
rate + rate = together rate
1/12 + 1/30 = 1/x
----
5x + 2x = 60
7x = 60
x = 8.57 hrs.
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x = 8 hr (0.57)60 minutes
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x = 8 hr 32 minutes (time to fill the pool when pipe and hose are used)
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Cheers,
Stan H.
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