A Tutor Promises to Improve GMAT Scores of Students by More

question 11

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.Which of the following hypotheses will determine if the students improved their test scores by more than 50 points after being tutored?

• A) H₀: µ_D ≤ 0,H_A: µ_D > 0
• B) H₀: µ_D ≥ 0,H_A: µ_D <0
• C) H₀: µ_D ≤ 50,H_A: µ_D >50
• D) H₀: µ_D ≥ 50,H_A: µ_D <50

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Definitions:

Fixed Manufacturing Overhead

Ongoing, consistent expenses associated with manufacturing operations, such as rent, salaries, and utilities, regardless of production levels.

Denominator Level

The activity level chosen to compute the predetermined overhead rate, reflecting expected or actual activity.

Machine-Hours

A measurement of the amount of time machines are run during production, often used as a basis for allocating manufacturing overhead.

Fixed Overhead Budget

A fixed overhead budget outlines the expected costs of fixed overheads, such as salaries and rent, that are not influenced by changes in production volume.