A shareholders' group, in lodging a protest, claimed that the mean tenure for a chief executive office (CEO) was at least nine years. A survey of companies reported in The Wall Street Journal found a sample mean tenure of

x = 7.27 years

for CEOs with a standard deviation of

s = 6.38 years.

(a)

Formulate hypotheses that can be used to challenge the validity of the claim made by the shareholders' group.

H₀: > 9

H_a: 9

H₀: < 9

H_a: 9

H₀: = 9

H_a: 9

H₀: 9

H_a: < 9

H₀: 9

H_a: > 9

(b)

Assume 80 companies were included in the sample.

What is the test statistic? (Round your answer to three decimal places.)

What is the p-value for your hypothesis test? (Round your answer to four decimal places.)

p-value =

(c)

At

= 0.01,

what is your conclusion?

Do not reject H₀. We can conclude that the mean tenure of a CEO is significantly lower than 9 years. The claim of the shareholders group is not valid.

Do not reject H₀. We cannot conclude that the mean tenure of a CEO is significantly lower than 9 years. The claim of the shareholders group is valid.

Reject H₀. We cannot conclude that the mean tenure of a CEO is significantly lower than 9 years. The claim of the shareholders group is valid.

Reject H₀. We can conclude that the mean tenure of a CEO is significantly lower than 9 years. The claim of the shareholders group is not valid.