document.write( "Question 1097855: Bob and Sarah need to paint a fence. Bob can paint a fence in 4 hours and Sarah can paint a fence in 2.5 hours. If they work together, how long will it take them to paint the fence? \n" ); document.write( "
Algebra.Com's Answer #712276 by greenestamps(13200)\"\" \"About 
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Here is an alternative method that I see many students preferring over the method shown in the two previous responses.

\n" ); document.write( "(1) Multiply the times it takes the two of them alone to do the job: \"2.5%2A4+=+10\"

\n" ); document.write( "In 10 hours, Bob could paint 2.5 of those fences, and Sarah could paint 4 of them. So in 10 hours the 2 of them together could paint 6.5 fences.

\n" ); document.write( "Then the number of hours they would need together to paint the one fence is \"10%2F6.5+=+20%2F13\"
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