document.write( "Question 719994: Will can paint six rooms in 12 hours working alone If his friend Matthew helps him together they can paint the six rooms in 7 hours How long would it take Matthew to paint the 6 rooms by himself? \n" ); document.write( "

Algebra.Com's Answer #441619 by josmiceli(19441) $\"\"$ $\"About$

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The problem only talks about 6 rooms, so
\n" ); document.write( "I can call painting 6 rooms 1 job
\n" ); document.write( "Let $\"+t+\"$ = the time in hrs for Matthew to
\n" ); document.write( "do 1 job by himself
\n" ); document.write( "Add their rates of painting to get their rate
\n" ); document.write( "painting together
\n" ); document.write( "( 1 job ) /( 12 hrs ) + ( 1 job ) / ( t hrs ) = ( 1 job ) / ( 7 hrs )
\n" ); document.write( " $\"+1%2F12+%2B+1%2Ft+=+1%2F7+\"$
\n" ); document.write( "Multiply both sides by $\"+7%2A12%2At+\"$
\n" ); document.write( " $\"+7t+%2B+7%2A12+=+12t+\"$
\n" ); document.write( " $\"+5t+=+84+\"$
\n" ); document.write( " $\"+t+=+16.8+\"$
\n" ); document.write( "matthew can do the job in 16.8 hrs by himself
\n" ); document.write( "check answer:
\n" ); document.write( " $\"+1%2F12+%2B+1%2F16.8+=+1%2F7+\"$
\n" ); document.write( " $\"+.08333++%2B+.05952+=+.14286+\"$
\n" ); document.write( " $\"+.14285+=+.14286+\"$
\n" ); document.write( "close enough\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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