document.write( "Question 1003343: alan, bill, cathy, and debbie work at a sub shop. It takes alan 2 minutes to make 1 sub alone. When working together , alan and bill can make 5 subs in 6 minutes, bill and cathy can make 7 subs in 12 mintues, and cathy and debbie can make 9 subs in 20 minutes. If all four employees work together , how many subs can they make in an hour? \n" ); document.write( "

Algebra.Com's Answer #620084 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let their rates of working = Ra, Rb, Rc, and Rd
\n" ); document.write( " $\"+R%5Ba%5D+=+1%2F2+\"$ ( he makes 1 sub in 2 min )
\n" ); document.write( " $\"+R%5Ba%5D+%2B+R%5Bb%5D+=+5%2F6+\"$
\n" ); document.write( " $\"+R%5Bb%5D+%2B+R%5Bc%5D+=+7%2F12+\"$
\n" ); document.write( " $\"+R%5Bc%5D+%2B+R%5Bd%5D+=+9%2F20+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "Adding the 2nd and 4th equations:
\n" ); document.write( " $\"+R%5Ba%5D+%2B+R%5Bb%5D+%2B+R%5Bc%5D+%2B+R%5Bd%5D+=+5%2F6+%2B+9%2F20+\"$
\n" ); document.write( " $\"+R%5Ba%5D+%2B+R%5Bb%5D+%2B+R%5Bc%5D+%2B+R%5Bd%5D+=+50%2F60+%2B+27%2F60+\"$
\n" ); document.write( " $\"+R%5Ba%5D+%2B+R%5Bb%5D+%2B+R%5Bc%5D+%2B+R%5Bd%5D+=+77%2F60+\"$
\n" ); document.write( "All 4 together can make 77 subs in 1 hour \n" ); document.write( "

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