document.write( "Question 414561: One machine can turn out 1000 pieces in 12 days. A second machine takes 18 days to turn out 1000 pieces. On a particular run the first machine operated for 4 days alone. The second machine was then put into operation, and the two worked together. How long did it take to finish 1000 pieces \n" ); document.write( "
Algebra.Com's Answer #290849 by ankor@dixie-net.com(22740)\"\" \"About 
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One machine can turn out 1000 pieces in 12 days.
\n" ); document.write( " A second machine takes 18 days to turn out 1000 pieces.
\n" ); document.write( " On a particular run the first machine operated for 4 days alone.
\n" ); document.write( " The second machine was then put into operation, and the two worked together.
\n" ); document.write( " How long did it take to finish 1000 pieces?
\n" ); document.write( ":
\n" ); document.write( "Let t = time that the two machines worked together
\n" ); document.write( ":
\n" ); document.write( "Let the completed job = 1 (1000 pieces made)
\n" ); document.write( ":
\n" ); document.write( "Mach 1 + Mach 2
\n" ); document.write( "\"%28t%2B4%29%2F12\" + \"t%2F18\" = 1
\n" ); document.write( "Multiply eq by 26 to clear the denominators, results:
\n" ); document.write( "3(t+4) + 2t = 36
\n" ); document.write( ":
\n" ); document.write( "3t + 12 + 2t = 36
\n" ); document.write( "5t = 36 - 12
\n" ); document.write( "5t = 24
\n" ); document.write( "t = \"24%2F5\"
\n" ); document.write( "t = 4.8 days working together to finish the job
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check this: (Machine 1 worked 8.8 days)
\n" ); document.write( "8.8/12 + 4.8/18 =
\n" ); document.write( ".733 + .267 = 1.0 confirms our solution of 4.8 days working together
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