Use the Following to Answer Questions

question 48

Multiple Choice

Use the following to answer questions :
A company that manufactures light bulbs claims that its light bulbs last an average of 1,150 hours.A sample of 25 light bulbs manufactured by this company gave a mean life of 1,097 hours and a standard deviation of 133 hours.A consumer group wants to test the hypothesis that the mean life of light bulbs produced by this company is less than 1,150 hours.The significance level is 5%.Assume the population is normally distributed.
-What is the critical value of t?

• A)-1.704
• B)-1.711
• C)-2.797
• D)-2.787

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Definitions:

Average Tax Rate

The ratio of the total amount of taxes paid to the total tax base (taxable income or spending), expressing the percentage of income that is paid in taxes.

Income

Monetary payment received for work, from investments, or from government benefits, contributing to an individual's wealth.

Marginal Tax Rate

The tax rate applied to the last dollar of income, showing the percentage of additional income that is paid in tax.

Income

The amount of money or value received, typically on a regular basis, for work or through investments.