document.write( "Question 755495: Can you help me with this problem? Jill and Sarah are mowing a lawn together (with separate mowers). It will take them 2 1/2 hours to complete. If Jill (by herself) can mow the same lawn in 4 hours, how long would it take Sarah to mow the lawn by herself? \n" ); document.write( "
Algebra.Com's Answer #459681 by stanbon(75887)\"\" \"About 
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Jill and Sarah are mowing a lawn together (with separate mowers). It will take them 2 1/2 hours to complete. If Jill (by herself) can mow the same lawn in 4 hours, how long would it take Sarah to mow the lawn by herself?
\n" ); document.write( "------
\n" ); document.write( "Together DATA: time = 5/2 hrs/job ; rate = 2/5 job/hr
\n" ); document.write( "-------
\n" ); document.write( "Jill DATA::::: time = 4 hrs/job ; rate = 1/4 job/hr
\n" ); document.write( "-------
\n" ); document.write( "Sarah DATA:::: time = x hrs/job ; rate = 1/x job/hr
\n" ); document.write( "=======================
\n" ); document.write( "Equation:
\n" ); document.write( "rate + rate = together rate
\n" ); document.write( "1/x + 1/4 = 2/5
\n" ); document.write( "-------
\n" ); document.write( "Multiply thru by 20x to get:
\n" ); document.write( "20 + 5x = 8x
\n" ); document.write( "3x = 20
\n" ); document.write( "x = 20/3 = 6 2/3 hrs (time for Sarah to do the job alone)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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