document.write( "Question 1198854: Quiboy can clean the barn in 6 hours, and Quiboy and Rod together can clean the same barn in 3 hours. How long would it take for Rod to clean the barn by himself? \n" ); document.write( "
Algebra.Com's Answer #832532 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "The jump from 6 hours to 3 hours is \"times 1/2\".\r
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\n" ); document.write( "\n" ); document.write( "This strongly suggests the two people work at the same rate, and take the same amount of time.
\n" ); document.write( "This is because they split the work in half (thereby cutting their worktime in half as well).\r
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\n" ); document.write( "\n" ); document.write( "We can think of it like saying the task is to move 60 bales of hay.
\n" ); document.write( "Quiboy needs 6 hours to do the job by himself.
\n" ); document.write( "His unit rate is 60/6 = 10 bales per hour.\r
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\n" ); document.write( "\n" ); document.write( "When working together, the two men can do the job in 3 hours.
\n" ); document.write( "Their combined rate is 60/3 = 20 bales per hour.
\n" ); document.write( "This of course assumes neither worker hinders the other.\r
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\n" ); document.write( "\n" ); document.write( "Quiboy offers 10 bales per hour, and the total combined rate is 20 bales per hour.
\n" ); document.write( "Rod offers the remaining 20-10 = 10 bales per hour.
\n" ); document.write( "His rate is the same as Quiboy. So he takes the same amount of time.\r
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\n" ); document.write( "\n" ); document.write( "If you wish to use algebra, then,
\n" ); document.write( "x = time (in hours) needed for Rod to do the job alone\r
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\n" ); document.write( "\n" ); document.write( "1/6 = Quiboy's unit rate
\n" ); document.write( "1/x = Rod's unit rate
\n" ); document.write( "1/3 = combined unit rate\r
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\n" ); document.write( "\n" ); document.write( "1/6 + 1/x = 1/3
\n" ); document.write( "x/(6x) + 6/(6x) = 1/3
\n" ); document.write( "(x+6)/(6x) = 1/3
\n" ); document.write( "3(x+6) = 6x*1
\n" ); document.write( "3x+18 = 6x
\n" ); document.write( "18 = 6x-3x
\n" ); document.write( "18 = 3x
\n" ); document.write( "3x = 18
\n" ); document.write( "x = 18/3
\n" ); document.write( "x = 6\r
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\n" ); document.write( "\n" ); document.write( "Or you could say
\n" ); document.write( "1/6 + 1/x = 1/3
\n" ); document.write( "6x * ( 1/6+1/x ) = 6x*( 1/3 )
\n" ); document.write( "6x*(1/6) + 6x*(1/x) = 6x*( 1/3 )
\n" ); document.write( "x + 6 = 2x
\n" ); document.write( "6 = 2x-x
\n" ); document.write( "6 = x
\n" ); document.write( "x = 6\r
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\n" ); document.write( "\n" ); document.write( "In my opinion an algebraic approach is a bit overkill.
\n" ); document.write( "Despite that, it's still handy to know this pathway and get practice.\r
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\n" ); document.write( "\n" ); document.write( "Answer: 6 hours
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