The Officejet printer can print a dissertation in 10 minutes. It takes the Deskjet printer 16 min to copy the same document. If the two machines work together, how many minutes will it take to copy the document?
In 160 minutes, the deskjet does 10, and the officejet does 16.
so the combined rate is 26/160
combined rate=.1625 copies/minute
time=1copy/rate= 1/.1625 or 6.2min