The Average Time Before Breakdown of a Machine Is Normally

question 11

Multiple Choice

The average time before breakdown of a machine is normally distributed and has a mean of nine weeks and a standard deviation of 1.5 weeks. If breakdown cost averages $1,500 and preventive maintenance costs $500, what is the optimal preventive maintenance interval?

• A)3.8 weeks
• B)8.4 weeks
• C)9.6 weeks
• D)6.9 weeks
• E)7.2 weeks

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Definitions:

Shares Sold

Refers to the number of shares of stock that have been bought and sold by investors over a given period, indicating trading activity and liquidity.

Dividends

Corporate profits shared with shareholders in the form of monetary disbursements.

Significant Influence

The power to participate in the financial and operating policy decisions of a business, but not control them completely, typically associated with ownership of between 20% and 50% of voting stock.

Fair-value Method

An accounting strategy used for valuing and assessing assets and liabilities based on current market prices or estimates.