document.write( "Question 160986: One person can do a job in 8 hours. A second person can do it in 12 hours. If the first person works 2 hours less than the second, how many hours will it take them working together?\r
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Algebra.Com's Answer #118636 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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One person can do a job in 8 hours. A second person can do it in 12 hours. If the first person works 2 hours less than the second, how many hours will it take them working together?
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\n" ); document.write( "Let t = time that they worked together
\n" ); document.write( "then
\n" ); document.write( "(t+2) = total time worked by the 2nd person
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\n" ); document.write( "Let the completed job = 1
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\n" ); document.write( "Each will do a fraction of the work which will add up to 1:
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\n" ); document.write( "1st person + 2nd person = completed job
\n" ); document.write( " $\"t%2F8\"$ + $\"%28%28t%2B2%29%29%2F12\"$ = 1
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\n" ); document.write( "Multiply equation by 24 to get rid of the denominator, rsults:
\n" ); document.write( "3t + 2(t+2) = 24
\n" ); document.write( "3t + 2t + 4 = 24
\n" ); document.write( "3t + 2t = 24 - 4
\n" ); document.write( "5t = 20
\n" ); document.write( "t = $\"20%2F5\"$
\n" ); document.write( "t = 4 hrs working together
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\n" ); document.write( "Check solution:
\n" ); document.write( "4/8 + 6/12 = 1 \n" ); document.write( "

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