Question

A statistics instructor is interested in determining whether or not a review session improved student performance on the final exam. The review session was administered to a sample of students (n=32) in an attempt to determine if this has a positive effect on exam performance. Based on information gathered in previous semesters, the population mean for the final exam is 75.2. The sample mean obtained from the 32 students is 80 with a sample standard deviation of 12.  

Use a 0.01 significance level to test the instructor's claim that the review session improved student performance on the final exam.

Round all answers to 3 decimal places.

Test Statistic =

p-value =

Reject the null hypothesis (yes/no)

Is there sufficient evidence to support the instructors claim that the review session improved student performance on the final exam (yes/no)?

Answer 1

This is the two tailed test .

The null and alternative hypothesis is

H₀ : = 75.2

H_a : 75.2

Test statistic = t

= ( - ) / s / n

= (80 - 75.2) / 12 / 32

Test statistic = 2.263

df = 31

P-value = 0.031

Reject > NO

Is there sufficient evidence > NO