Question 187064
The time required to fill a pool with a water hose is 30 hours. Using a pump the pool can be filled in 10 hours. How long will it take to fill the pool using a pump and 2 hoses?
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Let t = time required when two hoses and a pump are used
Let full pool = 1
:
{{{(2t)/30}}} + {{{t/10}}} = 1
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In the pool problem above how long would it take to fill the pool if the drain, which could drain the pool in 15 hours, is left open?
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Same thing but subtract for the drain
{{{(2t)/30}}} + {{{t/10}}} - {{{t/15}}}= 1