SOLUTION: a new machine that deposits cement for a road requires 12 hours to complete one-half mile section of the road.an older machine requires 16 hours to pave the same amount of road. af

Question 1184485: a new machine that deposits cement for a road requires 12 hours to complete one-half mile section of the road.an older machine requires 16 hours to pave the same amount of road. after depositing cement for 4 hours, the new machine develops mechanical problem and quits working. the older machine is brought into place and continues the job.how long in hours does it take the older machine to complete the job?
Answer by josgarithmetic(39620) (Show Source): You can put this solution on YOUR website!
The way the description is made, the two machines do not operate together at the same time. The only the new machine first is used, and then only the old machine is used.

The job seems to be, "complete one-half mile of cement road". That is the ONE job.

x, the amount of time the old machine was in use.

Simplify and solve.
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