A Group of Statistics Students Decided to Conduct a Survey

question 52

Multiple Choice

A group of statistics students decided to conduct a survey at their university to find the average (mean) amount of time students spent studying per week. Assuming a population standard deviation of 3 hours, what is the required sample size if the error should be less than ½ hour with a 99% level of confidence?

• A) 196
• B) 240
• C) 15
• D) 16

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Definitions:

Variable Costing

An accounting method that includes only variable production costs (direct materials, direct labor, and variable manufacturing overhead) in the cost of a unit of product.

Unit Product Cost

The calculated cost to produce one unit of a product, including direct materials, labor, and overhead.

Contribution Margin

The amount remaining from sales revenue after variable costs have been deducted, indicating how much contributes to covering fixed costs and generating profit.

Variable Costing

A costing method that includes only variable manufacturing costs—direct materials, direct labor, and variable manufacturing overhead—in the cost of a unit of product.