document.write( "Question 1036207: Five brick-layers working together can build a wall in 20 days.
\n" ); document.write( "Suppose every brick-layer works at the same rate. Three
\n" ); document.write( "brick-layers work on the wall for 10 days before eleven more
\n" ); document.write( "brick-layers join them. How much longer will it take them to
\n" ); document.write( "finish the wall? \n" ); document.write( "
Algebra.Com's Answer #650841 by Edwin McCravy(20055)\"\" \"About 
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Five brick-layers working together can build a wall in 20 days.
\n" ); document.write( "Suppose every brick-layer works at the same rate. Three
\n" ); document.write( "brick-layers work on the wall for 10 days before eleven more
\n" ); document.write( "brick-layers join them. How much longer will it take them to
\n" ); document.write( "finish the wall?\r
\n" ); document.write( "\n" ); document.write( "Suppose every brick-layer works at the same rate.
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document.write( "Let the rate of 1 brick-layer be R in walls per day.\r\n" );
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document.write( "Then \r\n" );
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document.write( "(rate)(time) = (fraction of wall completed) \r\n" );
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\n" ); document.write( "Five brick-layers working together can build a wall in 20 days.
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\r\n" );
document.write( "The rate of 1 brick-layer is R so the rate of 5 \r\n" );
document.write( "brick-layers is 5R\r\n" );
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document.write( "(rate)(time) = (fraction of wall completed),so\r\n" );
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document.write( "(5R)(20) = 1\r\n" );
document.write( "    100R = 1\r\n" );
document.write( "       R = 1/100 of a wall per day.\r\n" );
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\n" ); document.write( "Three brick-layers work on the wall for 10 days...
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document.write( "The rate of 1 brick-layer is 1/100 so the rate of 3 \r\n" );
document.write( "brick-layers is 3/100\r\n" );
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document.write( "(rate)(time) = (fraction of wall completed)\r\n" );
document.write( "(3/100)(10)  = 3/10 of the wall completed\r\n" );
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document.write( "So there's still 7/10 of the wall left to go.\r\n" );
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\n" ); document.write( "...before eleven more brick-layers join them.
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document.write( "That makes 14 brick-layers  \r\n" );
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document.write( "The rate of 1 brick-layer is 1/100 so the rate of 14 \r\n" );
document.write( "brick-layers is 14/100\r\n" );
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\n" ); document.write( "How much longer will it take them to finish the wall?
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document.write( "Let the answer be x days for the 14 to finish the remaining \r\n" );
document.write( "7/10 of the wall.\r\n" );
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document.write( "(rate)(time) = (fraction of wall completed)\r\n" );
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document.write( "(14/100)(x)  = 7/10 \r\n" );
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document.write( "Multiply both sides by 100\r\n" );
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document.write( "14x = 70\r\n" );
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document.write( "x = 5 more days.\r\n" );
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document.write( "Edwin
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