8:00 -- 15:30, is 7.5 hours

(no break for lunch? Where's the union steward?)

117 workers times 7.5 hours divided by 12 hrs per car means that 73.1 cars can be produced this shift.

Target 100 cars:

100 cars times 12 hrs per car means 1200 labor hours.

1200 hours divided by 117 workers is a 10.25 hour shift.

Add 10.25 hours to the start time will give the end of shift time.

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