document.write( "Question 129133: One printer can print the paychecks for the employees of a company in 54 min. A second printer can print the checks in 81 min. How long would it take to print the checks with both printers operating? \n" ); document.write( "
Algebra.Com's Answer #94392 by bucky(2189)\"\" \"About 
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If the first printer can print all the checks in 54 minutes, then each minute it prints
\n" ); document.write( "\"1%2F54\" of the checks. So all you have to do is multiply this rate and you can find the
\n" ); document.write( "number of checks it has printed. For example, in 5 minutes this printer will print \"5%2A1%2F54+=+5%2F54\"
\n" ); document.write( "So in 5 minutes this printer would print 5 fifty-fourths of the checks. And in t minutes this
\n" ); document.write( "printer will print \"t%2A%281%2F54%29+=+t%2F54\" of the checks.
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\n" ); document.write( "Similarly the each minute that goes by the other printer prints \"1%2F81\" of the checks and
\n" ); document.write( "in t minutes the other printer prints \"t%2F81\" of the checks.
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\n" ); document.write( "You can now add these two amounts of check printing together and set them equal to the 1 entire
\n" ); document.write( "job. So you have the equation:
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\n" ); document.write( "\"t%2F54+%2B+t%2F81+=+1\"
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\n" ); document.write( "You can get rid of the denominators by first multiplying both sides of this equation (all
\n" ); document.write( "terms) by 54. When you multiply each term by 54 you get:
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\n" ); document.write( "\"t+%2B+54t%2F81+=+54\"
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\n" ); document.write( "Next get rid of the other denominator by multiplying both sides of this equation (all terms)
\n" ); document.write( "by 81 to get:
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\n" ); document.write( "\"81t+%2B+54t+=+54%2A81\"
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\n" ); document.write( "On the left side add the two terms to get:
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\n" ); document.write( "\"135t+=+54%2A81\"
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\n" ); document.write( "And multiply out the right side to make the equation become:
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\n" ); document.write( "\"135t+=+4374\"
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\n" ); document.write( "Divide both sides by 135 and you find that the equation is reduced to:
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\n" ); document.write( "\"t+=+4374%2F135+=+32.4\"
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\n" ); document.write( "So when both printers work together, they can complete all the payroll checks in 32.4 minutes.
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\n" ); document.write( "Hope this helps you to understand the problem and how to work it.
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