SOLUTION: printing machine A can do printing in 8 hours. With the machine B the same printing would take 12 hours. It was decided that both machines will be used for the printing. However, a

Question 905924: printing machine A can do printing in 8 hours. With the machine B the same printing would take 12 hours. It was decided that both machines will be used for the printing. However, after a while the machine A broke down. After that it took 6 hours to finish the printing with machine B. How many hours did the machine A print before it broke down?
Answer by josgarithmetic(39614) (Show Source): You can put this solution on YOUR website!
RATES JOB/HOUR
Machine A,
Machine B,
CombinedAB,

RT=J Uniform Rate rule for doing a job

The job is split into two time quantities. The combined machines part for unknown t time and then the machine B part which was 6 hours.

, doing ONE job.

2 hours 24 minutes, time that A and B worked together before A quit.
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