A Tutor Promises to Improve GMAT Scores of Students by More

question 21

Multiple Choice

A tutor promises to improve GMAT scores of students by more than 50 points after three lessons. To see if this is true, the tutor takes a sample of 49 students' test scores after and before they received tutoring. The mean difference was 53 points better after tutoring, with a standard deviation of the difference equal to 12 points. Let µ_D denote the mean of the difference: score after tutoring minus score before tutoring. Assuming α = 0.05, which of the following is the appropriate critical value?

• A) z = 1.677
• B) z = 2.011
• C) t_0.05,48 = 1.677
• D) t_0.05,₄₈ = 2.011

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Definitions:

Creditors' Meeting

A gathering organized during the bankruptcy process where creditors can question the debtor about their finances and the proposed plans for reorganizing or settling debts.

Bankruptcy

A legal status for individuals or entities that cannot repay the debts they owe, allowing them to seek relief through court intervention.

Dischargeable Debts

Debts that can be eliminated through bankruptcy, relieving the debtor from any further obligation for these debts.

Chapter 13

A chapter of the U.S. Bankruptcy Code allowing individuals with regular income to develop a plan to repay all or part of their debts.