An office has an old copying machine and a new one. Working together, it takes both
Chapter 6, Problem 45(choose chapter or problem)
An office has an old copying machine and a new one. Working together, it takes both machines 6 hours to make all the copies of the annual financial report. Working alone, it takes the old copying machine 5 hours longer than the new one to make all the copies of the report. How long would it take the new copying machine to make all the copies working alone?
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