document.write( "Question 33687This question is from textbook Algebra 1
\n" ); document.write( ": It takes 10 hours to fill a pool with water, and 20 hours to drain it. If the pool is empty and the drain is open, how long will it take to fill the pool? \n" ); document.write( "

Algebra.Com's Answer #20101 by Earlsdon(6294) $\"\"$ $\"About$

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In 1 hour, you can fill 1/10 of the pool and in 1 hour you can empty 1/20 of the pool. If the two events occur simultaneously, then in 1 hour you can fill 1/10 - 1/20 = 1/20 of the pool.
\n" ); document.write( "So, at this rate, it will take 20 hours to fill the pool with the drain open. \n" ); document.write( "

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