What Is the 90% Confidence Interval for the Variance of Exam

question 11

Multiple Choice

What is the 90% confidence interval for the variance of exam scores for 28 algebra students, if the standard deviation of their last exam was 12.7?

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Definitions:

Net Income

The residue of all revenues and gains minus all expenses and losses for a period, often known as the bottom line.

Sales

The total amount of income generated by the selling of goods or services by a company during a certain period.

Manufacturing Costs

Refers to the total expenses incurred in the process of producing a product, including raw materials, labor, and overhead costs.

Variable Costing

An accounting method that only includes variable production costs (direct materials, direct labor, and variable manufacturing overhead) in product costs, treating fixed costs as period expenses.