document.write( "Question 235462: If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together? \n" ); document.write( "
Algebra.Com's Answer #173419 by Alan3354(69443)\"\" \"About 
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If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together?
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\n" ); document.write( "S does 1/4 house per hour
\n" ); document.write( "J does 1/6 house per hour
\n" ); document.write( "Together, they do 1/4 + 1/6 per hour
\n" ); document.write( "= 3/12 + 2/12 = 5/12 house per hour
\n" ); document.write( "--> 12/5 hours per house
\n" ); document.write( "= 2.4 hours
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\n" ); document.write( "Use the shortcut for these, product/sum
\n" ); document.write( "4*6/(4+6) = 24/10
\n" ); document.write( "= 2.4
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