Problema Solution
the OfficeJet printer can copy Maria's dissertation in 18 min. The LasterJet printer can copy the same documents in 10 min. if the two machines work together, hot long would they take to copy the dissertation?
Answer provided by our tutors
let 'x' be the time in minutes needed to copy the dissertation with the 2 printers working
the rate of the OfficeJet printer is 1/18
the rate of the LasterJet printer is 1/10
the rate of the both printers is 1/x
thus we have
1/18 + 1/10 = 1/x
by solving we get
x = 45/7
x = 6.43 min
click here to see the step by step solution of the equation
it take 6.43 minutes for the both printers to copy Maria's dissertation.