From Past Records It Is Known That the Average Life

question 41

Multiple Choice

From past records it is known that the average life of a battery used in a digital clock is 305 days. The battery life is normally distributed. The battery was recently modified to last longer. A sample of 20 of the modified batteries was tested. It was discovered that the mean life was 311 days and the sample standard deviation was 12 days. We want to test at the 0.05 level of significance whether the modification increases the life of the battery. What is our decision rule?

• A) Do not reject the null hypothesis if computed t is 1.96 or greater
• B) Reject the null hypothesis if computed t is less than 1.96
• C) Do not reject the null hypothesis if computed t is 1.729 or greater
• D) Reject the null hypothesis if computed t is 2.086 or greater
• E) None of these statements are true

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Definitions:

Original Cost

The amount initially paid for an asset, not accounting for depreciation, inflation, or market value adjustments.

Short-Term Note

A debt instrument with a maturity of less than one year, used by companies to finance short-term obligations.

Legal Fees

Charges incurred for legal services provided by attorneys or law firms.

Delinquent Taxes

Taxes that have not been paid by the due date, often incurring penalties and interest.