Math
posted by Sue .
The officejet printer can copy Sue's dissertation in 18 min. The laserjet printer can copy the same document in 22 min. If the two machines work together how long would they take to copy the dissertation?
Any help would be greatly appreciated.

Math 
bobpursley
In 18*22min, laserjet can do 22, and the officejet can do 18. So the rate is
rate= number/time= (18+22)/22*18=40/396min = 1dissertation/9.9 min
that answers it, but formally
dissertations= rate*time
time= dissertations/rate= 1dissertation/(1dissertation/9.9min)= 9.9 min 
Math 
Sue
Would it be 99/10?

Math 
Sue
Thank you for your help.

Math 
bobpursley
yes, but few folks say 99/10 min, most would say 9.9 minutes, or 9 minutes 54seconds.
Respond to this Question
Similar Questions

algebra
the officejet printer can copy lisa's dissertation in 18 min. the laserjet printer can copy the same document in 20 min. if the two machines work together, how long would the take to copy the dissertation 
math
the officejet printer can copy lisa's dissertation in 18 min. the laserjet printer can copy the same document in 20 min. if the two machines work together, how long would the take to copy the dissertation 
math
the officejet printer can copy Janet's dissertation in 10 minutes. The laserjet printer can print the same copy in 20 minutes. If the two machines work together, how long would they take to copy the dissertation? 
algebra
The OfficeJet printer can copy Maria's dissertation in 18 min. The LaserJet printer can copy the same documents in 14 min. If the two machines work together, how long would they take to copy the dissertation? 
algebra
the officejet printer can copy maria's dissertation in 18 min. The laserjet printer can copy the same document in 22 min. If the two machines work together, how long would they take to copy the dissertation? 
Algebra
The Office Jet printer can copy Janet's dissertation in 20 min. The Laser Jet printer can copy the same documents in 12 min. If the two machines work together, how long would they take to copy the dissertation? 
Algebra/Time
The officejet printer can copy Lisa's dissertation in 22 min. The laserjet printer can copy the same document in 18 min. If the two machines work together, how long would they take to print the document? 
algebra
the office jet printer can copy maria's dissertation in 16 min. the jet printer can copy the same document is 8 min if the two machines work together how long would they take to copy the dissertation 
Algebra
The officejet printer can copy sues dissertation in 16 minutes. The laser printer can copy the same document in 22 minutes. If the two machines work together, how long would they take to copy the dissertation? 
Algebra
The officejet printer can copy sues dissertation in 16 minutes. The laser printer can copy the same document in 22 minutes. If the two machines work together, how long would they take to copy the dissertation?