document.write( "Question 334019: Working alone, it takes Heather 13 hours to tar a roof. Lea can tar the same roof in 15 hours. If they worked together how long would it take them?\r
\n" ); document.write( "\n" ); document.write( "The answer is 6.96 hours (I looked at the answer sheet! Shhh!), but I need to know how to solve it! And i have to show all of my work!
\n" ); document.write( "Help? Thank you so MUCH!!! \n" ); document.write( "

Algebra.Com's Answer #239316 by Edwin McCravy(20077) $\"\"$ $\"About$

You can put this solution on YOUR website!
Working alone, it takes Heather 13 hours to tar a roof. Lea can tar the same roof in 15 hours. If they worked together how long would it take them?\r
\n" ); document.write( "\n" ); document.write( "The answer is 6.96 hours (I looked at the answer sheet! Shhh!), but I need to know how to solve it! And i have to show all of my work!
\n" ); document.write( "Help? Thank you so MUCH!!!
\n" ); document.write( "

\r\n" );
document.write( "Make this chart:\r\n" );
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document.write( "                      |Number of roofs tarred |Time required |Rate in roofs/hr\r\n" );
document.write( "Heather working alone |                       |              | \r\n" );
document.write( "Lea working alone     |                       |              | \r\n" );
document.write( "Both working together |                       |              |  \r\n" );
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\n" ); document.write( "Working alone, it takes Heather 13 hours to tar 1 roof
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\r\n" );
document.write( "Therefore fill in 13 hours for her time, and 1 for the number of roofs tarred.\r\n" );
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document.write( "                      |Number of roofs tarred |Time required |Rate in roofs/hr\r\n" );
document.write( "Heather working alone |            1          |      13      | \r\n" );
document.write( "Lea working alone     |                       |              | \r\n" );
document.write( "Both working together |                       |              |  \r\n" );
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\n" ); document.write( "Lea can tar the same roof in 15 hours
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document.write( "Therefore fill in 15 for her time, and 1 for the number of roofs tarred.\r\n" );
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document.write( "                      |Number of roofs tarred |Time required |Rate in roofs/hr\r\n" );
document.write( "Heather working alone |            1          |      13      | \r\n" );
document.write( "Lea working alone     |            1          |      15      | \r\n" );
document.write( "Both working together |                       |              |  \r\n" );
document.write( "\r\n" );
document.write( "Fill in x for the time required for both working together, and 1 for the\r\n" );
document.write( "number of roofs tarred.\r\n" );
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document.write( "                      |Number of roofs tarred |Time required |Rate in roofs/hr\r\n" );
document.write( "Heather working alone |            1          |      13      |   \r\n" );
document.write( "Lea working alone     |            1          |      15      |   \r\n" );
document.write( "Both working together |            1          |       x      |   \r\n" );
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document.write( "Finish filling in the chart by using \r\n" );
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document.write( " \r\n" );
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document.write( "                      |Number of roofs tarred |Time required |Rate in roofs/hr\r\n" );
document.write( "Heather working alone |            1          |      13      |     1/13 \r\n" );
document.write( "Lea working alone     |            1          |      15      |     1/15\r\n" );
document.write( "Both working together |            1          |       x      |     1/x \r\n" );
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document.write( "Form the equation from:\r\n" );
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document.write( "{Heather's rate} + (Lea's rate) = (Rate of Both working together)\r\n" );
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document.write( "                     \r\n" );
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document.write( "Solve that and get  which does come out to 6.964285714\r\n" );
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document.write( "Edwin

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