document.write( "Question 1087237: it takes robert and william 12 hours to complete a history project. If Robert works alone on the same project for 16 hours and let william take over, william needs another 7 hours to complete it. How long does it take william to complete the history project alone?
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Algebra.Com's Answer #701627 by josgarithmetic(39621)\"\" \"About 
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\n" ); document.write( "...robert and william 12 hours to complete a history project. If Robert works alone on the same project for 16 hours and let william take over, william needs another 7 hours to complete it.
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\n" ); document.write( "\n" ); document.write( "\"system%281%2Fr%2B1%2Fw=1%2F12%2C%281%2Fr%2916%2B%281%2Fw%297=1%29\"\r
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\n" ); document.write( "\n" ); document.write( "BETTER APPROACH:
\n" ); document.write( "If use rates just as variables, not in a form of ratioinal numbers with times as denominators,...
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\n" ); document.write( "\n" ); document.write( "\"R=1%2F12-W\"\r
\n" ); document.write( "\n" ); document.write( "\"16%281%2F12-W%29%2B7W=1\"\r
\n" ); document.write( "\n" ); document.write( "\"16%2F12-16W%2B7W=1\"\r
\n" ); document.write( "\n" ); document.write( "\"4%2F3-9W=1\"\r
\n" ); document.write( "\n" ); document.write( "\"4%2F3-3%2F3=9W\"\r
\n" ); document.write( "\n" ); document.write( "\"1%2F3=9W\"\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28W=1%2F27%29\"\r
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\n" ); document.write( "\n" ); document.write( "William could do the whole job alone in 27 hours.
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