Assume That the Time Needed by a Worker to Perform

question 9

Short Answer

Assume that the time needed by a worker to perform a maintenance operation is normally distributed, with a mean of 60 minutes and a standard deviation of 6 minutes. What is the probability that the average time needed by a sample of 5 workers to perform the maintenance is between 63 and 68 minutes?

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Definitions:

Net Operating Income

The total profit of a company after operating expenses are subtracted, but before taxes and interest are deducted.

Average Operating Assets

The average value of the assets involved or used in the operating activities of a company over a given period, typically calculated as the average of the opening and closing balances of these assets.

Residual Income

Earnings that exceed the minimum required return on investment; it's what remains after all costs and expenses have been deducted.

Return on Investment

A performance measure used to evaluate the efficiency of an investment or compare the efficiency of a number of different investments, calculated as net profit divided by the cost of the investment.