A Cell Phone Service Provider Has Selected a Random Sample

question 47

Multiple Choice

A cell phone service provider has selected a random sample of 20 of its customers in an effort to estimate the mean number of minutes used per day. The results of the sample included a sample mean of 34.5 minutes and a sample standard deviation equal to 11.5 minutes. Based on this information, and using a 95 percent confidence level:

• A) the critical value is z = 1.96
• B) the critical value is z = 1.645
• C) the critical value is t = 2.093
• D) The critical value can't be determined without knowing the margin of error.

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Definitions:

MRP Curve

The marginal revenue product curve, which shows the additional revenue generated by one additional unit of an input.

Imperfectly Competitive Market

A market structure in which participants have some control over the prices because not all conditions of perfect competition are met, such as monopolistic competition and oligopoly.

Perfectly Competitive Market

A market structure characterized by many buyers and sellers, where no single party can influence the market price.

Complementary Resource

A good or service that enhances the value or performance of another primary product or service.