A Researcher Estimates the 90% CI for a Sample with a Mean

question 54

Multiple Choice

A researcher estimates the 90% CI for a sample with a mean of M = 8.9 and a standard error ( $\sigma$ _M) of 2.1.What is the confidence interval at this level of confidence?

• A) 90% CI 4.8, 13.0
• B) 90% CI 5.5, 12.4
• C) 90% CI 6.8, 11.0
• D) There is not enough information to answer this question.

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Definitions:

Business Segments

Distinct parts of a company that are engaged in different types of businesses, each of which may generate its own revenues and expenses.

Break-even Sales

The amount of revenue needed to be generated to cover all fixed and variable costs, indicating no profit or loss.

Wholesale Division

A division of a company that sells goods in large quantities to retailers, other distributors, or sometimes directly to consumers.

Fixed Expenses

Costs that do not change with the level of production or sales, such as rent, salaries, and insurance premiums.