document.write( "Question 905076: If Mary can paint a house in 4 hours and Dan can paint a house in 6 hours how long will it take them to paint a house together? \n" ); document.write( "

Algebra.Com's Answer #549002 by josmiceli(19441) $\"\"$ $\"About$

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Add their rates of painting
\n" ); document.write( "Mary's rate:
\n" ); document.write( "( 1 house ) / ( 4 hrs )
\n" ); document.write( "Dan's rate:
\n" ); document.write( "( 1 house ) / ( 6 hrs )
\n" ); document.write( "---------------------
\n" ); document.write( "Let $\"+t+\"$ = time in hrs to paint
\n" ); document.write( "the house working together
\n" ); document.write( " $\"+1%2F4+%2B+1%2F6+=+1%2Ft+\"$
\n" ); document.write( "Multiply both sides by $\"+12t+\"$
\n" ); document.write( " $\"+3t+%2B+2t+=+12+\"$
\n" ); document.write( " $\"+5t+=+12+\"$
\n" ); document.write( " $\"+t+=+1.4+\"$
\n" ); document.write( " $\"+.4%2A60+=+24+\"$
\n" ); document.write( "It will take them 1 hr 24 min working together
\n" ); document.write( " \n" ); document.write( "

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