Question

A student believes that the average grade on the statistics final examination was 87. A sample of 36 final examinations was taken. The average grade in the sample was 83.96 with a standard deviation of 12. The student wants to test whether the average is different from 87 at 90% level of confidence. Compute the p-value for this test.

NOTE: WRITE YOUR ANSWER WITH 4 DECIMAL DIGITS. DO NOT ROUND UP OR DOWN.

Answer 1

Null hypothesis, Hoi U = 87 Alternative hypothesis, Hail #87 sample size, n = 36 sample mean, X = 83.96 sample standard deviation, s = 12 Test statistie, t= X 4 = 83.96-87 slvo = -1.52 degrees of freedom = n-1= 36-1 = 35 This is a two-tailed test. ir p-value for this test = 2 P(+36 > 1-1.521) = 2 P (t36>1.52) = 0.137494 ~ 10.13741 (with a decimal digits)