Question

Consider the following hypotheses:

H₀: μ ≥ 220
H_A: μ < 220

A sample of 72 observations results in a sample mean of 209. The population standard deviation is known to be 18. (You may find it useful to reference the appropriate table: z table or t table)


a-1. Calculate the value of the test statistic. (Negative value should be indicated by a minus sign. Round intermediate calculations to at least 4 decimal places and final answer to 2 decimal places.)

a-2. Find the p-value.
A. 0.05  p-value < 0.10

B. p-value  0.10

C. p-value < 0.01

D. 0.01  p-value < 0.025

E. 0.025  p-value < 0.05

b. Does the above sample evidence enable us to reject the null hypothesis at α = 0.10?

A. Yes since the p-value is less than the significance level.

B. No since the p-value is greater than the significance level.

C. No since the p-value is less than the significance level.

D. Yes since the p-value is greater than the significance level.

c. Does the above sample evidence enable us to reject the null hypothesis at α = 0.01?

A. Yes since the p-value is less than the significance level.

B. Yes since the p-value is greater than the significance level.

C. No since the p-value is less than the significance level.

D. No since the p-value is greater than the significance level.

d. Interpret the results at α = 0.01.

A. We conclude that the population mean is less than 220.

B. We cannot conclude that the population mean is less than 220.

C. We conclude that the population proportion differs from 220.

D. We conclude that the population proportion equals 220.

Answer 1