document.write( "Question 1010359: Sam can stain his deck in 9 hours. His sister Grace can stain the deck in 12 hours. How many hours will it take them to stain the deck if they work together? \r
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Algebra.Com's Answer #625766 by josgarithmetic(39615)\"\" \"About 
You can put this solution on YOUR website!
The sum of their rates is their combined rate. Reciprocal of this rate is the time for \"staining his deck\".\r
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\n" ); document.write( "\n" ); document.write( "Sam stains his deck at the rate \"1%2F9\" deck per hours.
\n" ); document.write( "Grace stains the deck at the rate of \"1%2F12\" deck per hours.
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