document.write( "Question 1118379: an employment agency specializing in temporary construction help pays heavy equipment operators $1.20 per day and general laborers $91 per day if thirty-one people were hired and the payroll was $3339 how many heavy equipment operators were employed? how many laborers
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Algebra.Com's Answer #733672 by greenestamps(13209)\"\" \"About 
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\n" ); document.write( "It would be a good idea for you to look at what you have written before you send your question to us. $1.20 a day for heavy equipment operators? I don't think anybody would take that job.

\n" ); document.write( "So the real rate is clearly supposed to be $120 per day. Then we have
\n" ); document.write( "x heavy equipment operators at $120 per day and y general laborers at $91 per day, making 31 workers with a total pay of $3339 per day. Then

\n" ); document.write( "\"x%2By+=+31\"
\n" ); document.write( "\"120x%2B91y+=+3339\"

\n" ); document.write( "Unfortunately, when we try to solve that system of equations, we don't get answers that are whole numbers. So even after correcting your $1.20 per day to $120 per day, there is a flaw in your statement of the problem.

\n" ); document.write( "When I first read the problem, it occurred to me that we could solve the problem with logical analysis using only the total pay, without knowing the total number of workers.

\n" ); document.write( "Looking at the equation for total pay, we can see that the total pay for the heavy equipment operators will be a multiple of $10. Since the total pay is $3339 and the daily pay for the general laborers is $91, the number of general laborers must be a number ending in 9.

\n" ); document.write( "Then we could try 9, 19, 29,... as the number of general laborers and see which gives us a whole number for the number of heavy equipment operators.

\n" ); document.write( "But we can be even a little smarter than that. The total pay, $3339, is a multiple of 3, and the daily pay for the heavy equipment operators is a multiple of 3. Since the $91 daily pay for the general laborers is NOT a multiple of 3, the number of general laborers MUST be a multiple of 3.

\n" ); document.write( "That means the number of general laborers is either 9, or 39, or 69, or.... With the total pay being $3339, the only number that works is 9.

\n" ); document.write( "That gives us 9($91) = $819 for the total pay for the general laborers, leaving $3339-$819 = $2520 as the total pay for the heavy equipment operators. At $120 per day, the number of heavy equipment operators is then $2520/$120 = 21.

\n" ); document.write( "So the total number of workers is 9+21 = 30 -- NOT 31, as you say in your statement of the problem.
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