A Sample of 41 Light Bulbs Had a Mean Lifetime $95 \%$

question 96

Multiple Choice

A sample of 41 light bulbs had a mean lifetime of 599 hours. A $95 \%$ confidence interval for the population mean was $593.8 < \mu < 604.2$ .
Which one of the following statements is the correct interpretation of the results?

• A) None of these are true.
• B) The probability that the population mean is between 593.8 hours and 604.2 hours is 0.95.
• C) 95% of the light bulbs in the sample had lifetimes between 593.8 hours and 604.2 hours
• D) We are 95% confident that the mean lifetime of all the bulbs in the population is between 593.8 hours and 604.2 hours.

---

Definitions:

Units-of-Activity Method

A depreciation method where the expense is based on the number of units produced or the use of the asset, rather than the passage of time.

Double-Declining-Balance

An accelerated method of depreciation that doubles the normal depreciation rate to expense the asset more quickly.

Estimated Life

The expected duration over which an asset is likely to be useful or productive in its intended operation, used for depreciation purposes.

Straight-Line Depreciation

A method of allocating an asset's cost evenly across its useful life, resulting in the same depreciation expense each year.