document.write( "Question 1208990: A 5-horsepower (hp) pump can empty a pool in 5 hours.A smaller, 2-hp pump
\n" ); document.write( "empties the same pool in 8 hours. The pumps are used together to begin emptying
\n" ); document.write( "this pool.After two hours, the 2-hp pump breaks down. How long will it take the
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\n" ); document.write( "Let hp = horsepower
\n" ); document.write( "5hp = 1/5
\n" ); document.write( "2hp = 1/8
\n" ); document.write( "Let t = time in hours
\n" ); document.write( "1/t = time it takes larger pump to empty the pool
\n" ); document.write( "My equation is:
\n" ); document.write( "(1/5) + (1/8) = 1/t
\n" ); document.write( "Is this correct?
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Algebra.Com's Answer #847799 by AnlytcPhil(1806) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "A 5-horsepower (hp) pump can empty a pool in 5 hours.\r\n" );
document.write( "So the larger pump's emptying rate is  or \r\n" );
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document.write( "A smaller, 2-hp pump empties the same pool in 8 hours. \r\n" );
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document.write( "So the smaller pump's emptying rate is  or \r\n" );
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document.write( "The pumps are used together to begin emptying this pool.\r\n" );
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document.write( "Their rates add together so their combined rate is\r\n" );
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document.write( "After two hours,...     [the 2-hp pump breaks down.]\r\n" );
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document.write( "So RATE x TIME = FRACTION of the pool EMPTIED\r\n" );
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document.write( "Since 13/20ths of the pool has been emptied, there remain 7/20th of the pool\r\n" );
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document.write( "How long will it take the larger pump to empty the pool?\r\n" );
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document.write( "Now the TIME is an unknown, so we use a letter, say t:  \r\n" );
document.write( "Again, RATE x TIME = FRACTION of the pool EMPTIED, but now, we use only the rate\r\n" );
document.write( "of the larger pump, 1/5, and only the remaining 7/20 of the pool to be emptied.\r\n" );
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document.write( "So the equation is\r\n" );
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document.write( "Multiply both sides by 20\r\n" );
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document.write( " hours\r\n" );
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document.write( "1 hour and 45 minutes.\r\n" );
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document.write( "Edwin

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