The Expected (Mean)life of a Particular Type of Light Bulb

question 53

Multiple Choice

The expected (mean) life of a particular type of light bulb is 1,000 hours with a standard deviation of 50 hours.The life of this bulb is normally distributed.Which most closely reflects the probability that a randomly selected bulb would last fewer than 940 hours?

• A)0.3849
• B)0.8849
• C)0.1151
• D)0.6151
• E)0.6563

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Definitions:

Marginal Productivity Theory

An economic theory proposing that labor and other input costs are based on the marginal contribution of each input to the production process.

Income Distribution

The way in which total income is shared among individuals or groups in an economy.

Production Incentives

Motivational factors or rewards designed to encourage increased productivity or output by workers or companies.

Marginal Productivity Theory

An economic theory that explains income distribution based on the productivity of the factor inputs in producing goods and services.