document.write( "Question 1078031: Kim can paint the garage door in 2 hours and Jim can paint the same door in 1 hour. How long will it take them if they work together? \n" ); document.write( "

Algebra.Com's Answer #692502 by Edwin McCravy(20065) $\"\"$ $\"About$

You can put this solution on YOUR website!
Notice that the preceding answer 1.5 hrs, could not be correct because
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\n" ); document.write( "Jim down that much. LOL\r
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\n" ); document.write( "Kim can paint the garage door in 2 hours and Jim can paint the same door in 1 hour. How long will it take them if they work together?
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document.write( "You can do it with or without algebra.\r\n" );
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document.write( "Without algebra, just basic math:\r\n" );
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document.write( "If both work together for 2 hours painting garage doors\r\n" );
document.write( "(say in a new development of houses), Kim will paint\r\n" );
document.write( "1 garage door while Jim, the faster will paint 2 garage\r\n" );
document.write( "doors, so together they can paint 3 garage doors in 2 \r\n" );
document.write( "hours. So they can paint 1 garage door in 1/3 of 2 hours\r\n" );
document.write( "which is 1/3 of 120 minutes or 40 minutes.\r\n" );
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document.write( "With algebra:\r\n" );
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\n" ); document.write( "How long will it take them if they work together?
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Let the answer be x hours.\r\n" );
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\n" ); document.write( "Kim can paint the garage door in 2 hours.
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document.write( "So Kim's painting rate is 1 door per 2 hours or  or \r\n" );
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\n" ); document.write( "Jim can paint the same door in 1 hour
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document.write( "So Kim's painting rate is 1 door per 1 hour or  or \r\n" );
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document.write( "Together they can paint the same door in x hours:\r\n" );
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document.write( "So together their combined painting rate is 1 door per x hours or  or \r\n" );
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document.write( "The equation comes from:\r\n" );
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document.write( "Multiply through by 2x\r\n" );
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document.write( "2/3 of an hour is 2/3 of 60 minutes = 40 minutes.\r\n" );
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document.write( "Edwin

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