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fires

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A swimming pool can be filled in 36 hours using a garden hose and in 24 hours using a large diameter hose. Assuming that the flow rates through each hose are unaffected by the use of the other, how long will it take to fill the pool using both hoses at the same time?
 
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jazz519

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Re: what's the answer?

Volume of pool = Rate of change in vol from garden house x 36
Volume of pool = Rate of change in vol from large diameter hose x 24

Let these be equal

Rate of change in vol from garden house x 36 = rate of change in vol from large diameter hose x 24
therefore, 3 x Rate of change in vol from garden house = 2 x rate of change in vol from large diameter hose

So that means overall volume will be three parts from the large diameter house and two parts from the garden house

which means that it will take 2/5 x 36 or 3/5 x 24 hrs

which is 14.4 hrs
 

HeroWise

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I took a different approach, the above way is perfectly fine but i did it this way:

https://imgur.com/a/ioveU

PS: Funnily the randon String generator in the imgur link states "ioveU" lol
 

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