document.write( "Question 402162: Kindly answer this word problem:
\n" ); document.write( "Alex can do a piece of work in 20 days; Allen can do it in 24 days. After the two have been working together in 7 days, they are joined by Andy and the three finish the job in 3 more days. How long will it take Andy to do the job alone?\r
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Algebra.Com's Answer #284514 by nerdybill(7384)\"\" \"About 
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Alex can do a piece of work in 20 days; Allen can do it in 24 days. After the two have been working together in 7 days, they are joined by Andy and the three finish the job in 3 more days. How long will it take Andy to do the job alone?
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\n" ); document.write( "Amount of work done before Andy joins:
\n" ); document.write( "7(1/20 + 1/24)
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\n" ); document.write( "Let x = days it takes Andy to do the work by himself
\n" ); document.write( "then
\n" ); document.write( "7(1/20 + 1/24)+ 3(1/20 + 1/24 + 1/x) = 1
\n" ); document.write( "multiplying both sides by (20)(24)x:
\n" ); document.write( "7(24x + 20x)+ 3(24x + 20x + (20)(24)) = (20)(24)x
\n" ); document.write( "7(44x)+ 3(44x + 480) = 480x
\n" ); document.write( "308x+ 132x + 1440 = 480x
\n" ); document.write( "440x + 1440 = 480x
\n" ); document.write( "1440 = 40x
\n" ); document.write( "36 days = x\r
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