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
\n" ); document.write( "larger pump to empty the pool?
\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 #847538 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "A 5-horsepower (hp) pump can empty a pool in 5 hours.
\n" ); document.write( "A smaller, 2-hp pump empties the same pool in 8 hours.
\n" ); document.write( "The pumps are used together to begin emptying this pool.
\n" ); document.write( "After two hours, the 2-hp pump breaks down.
\n" ); document.write( "How long will it take the larger pump to empty the pool?\r
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\n" ); document.write( "\n" ); document.write( "Let hp = horsepower\r
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\n" ); document.write( "\n" ); document.write( "5hp = 1/5 \r
\n" ); document.write( "\n" ); document.write( "2hp = 1/8\r
\n" ); document.write( "\n" ); document.write( "Let t = time in hours \r
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\n" ); document.write( "\n" ); document.write( "1/t = time it takes larger pump to empty the pool\r
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\n" ); document.write( "\n" ); document.write( "My equation is:\r
\n" ); document.write( "\n" ); document.write( "(1/5) + (1/8) = 1/t\r
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\n" ); document.write( "\n" ); document.write( "Is this correct?
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\n" ); document.write( "\n" ); document.write( " It is wrong.\r
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\n" ); document.write( "\n" ); document.write( " I will show you a correct solution.\r
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document.write( "The rate of work of the 5hp pump is    of the job per hour.\r\n" );
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document.write( "The rate of work of the 2hp pump is    of the job per hour.\r\n" );
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document.write( "In 2 hours, the two pumps will make   +  of the job.\r\n" );
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document.write( "Let t be the time, in hours, for the 5hp pump to complete the job.\r\n" );
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document.write( "Then your setup equation is\r\n" );
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document.write( "     +  +  = 1,   which represents the whole job.\r\n" );
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document.write( "You should solve it for t.\r\n" );
document.write( "To do it, multiply everything by 5*8 = 40.  You will get\r\n" );
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document.write( "    2*8 + 2*5 + 8t = 40\r\n" );
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document.write( "       26     + 8t = 40\r\n" );
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document.write( "                8t = 40 - 26\r\n" );
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document.write( "                8t = 14\r\n" );
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document.write( "                 t = 14/8 = 1  hours = 1 hours = 1 hour and 45 minutes.\r\n" );
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document.write( "It is your ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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