document.write( "Question 871396: Eric can paint a room in 9 hours. Working together, Eric and Matt can paint the room in 4 hours. How long will it take Matt to paint the room by himself? \n" ); document.write( "
Algebra.Com's Answer #525505 by josgarithmetic(39618)\"\" \"About 
You can put this solution on YOUR website!
Their combined rate is the sum of their individual rates.\r
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\n" ); document.write( "\n" ); document.write( "\"1%2F9%2Br=1%2F4\", using r as Matt's rate. The rate unit is rooms per hour. Solve for r, and find the reciprocal. THAT is how long the time for Matt to paint the room himself.
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