An Educational Testing Service Designed an Achievement Test So That $$= 6 \sigma$$

question 8

Essay

An educational testing service designed an achievement test so that the range in student
scores would be greater than 300 points. To determine whether the objective was
achieved, the testing service gave the test to a random sample of 52 students and found
that the sample mean and variance were 733 and 2255, respectively. Specify the null and
alternative hypotheses for determining whether the test achieved the desired dispersion in
scores. Assume that range $$= 6 \sigma$$

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Definitions:

Dividend

A part of a company's profits paid out to its shareholders, often as cash or extra shares.

Treasury Stock

Shares that were issued and subsequently reacquired by the issuing corporation, reducing the amount of outstanding stock on the market.

Common Stock

A type of equity security that represents ownership in a corporation, giving shareholders voting rights and a share in profits.

Retained Earnings

The portion of a company's profits that is held back and not distributed to shareholders, reinvested in the business.