When rationing a technological operation (machining a p

When rationing a technological operation (machining a p

When rationing a technological operation (machining a part on a machine), the following results were obtained:

Operation execution time Number of workers

28 30 32 34 36 38 40 42

15 17 16 18 10 8 6 5

Determine the arithmetic mean and the coefficient of variation of the operation execution time.

Find the fashion and median.