document.write( "Question 54537This question is from textbook McDougal Littell Algebra 1 concepts and skills
\n" ); document.write( ": i do not understand how to even start this problem. it says:\r
\n" ); document.write( "\n" ); document.write( "With your new lawn mower, you can mow a lawn in 4 hours. With an older mower, your friend can mow the same lawn in 5 hours. How long will it take you to mow the lawn, working together?\r
\n" ); document.write( "\n" ); document.write( "HELP!
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Algebra.Com's Answer #36797 by Nate(3500)\"\" \"About 
You can put this solution on YOUR website!
Rate: 1/4
\n" ); document.write( "Time = t
\n" ); document.write( "Rate * Time = Work
\n" ); document.write( "t/4 = Work
\n" ); document.write( "Rate: 1/5
\n" ); document.write( "Time = t
\n" ); document.write( "Work = t/5
\n" ); document.write( "t/4 + t/5 = 1
\n" ); document.write( "20t/4 + 20t/5 = 20
\n" ); document.write( "5t + 4t + 20
\n" ); document.write( "9t = 20
\n" ); document.write( "t = 20/9
\n" ); document.write( "or 2 hours 13 minutes
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