Answer
$\bar{x}$ = 55, μ=58, $σ_\bar{s}$=$\frac{6}{\sqrt 70}$=0.7171, n=70
α = 0 , df = 70-1=69, critical value= 0
t =$\frac{\bar{x}-μ }{σ_\bar{s}}$= 55-58- 0.7171
= -4.18
for α = 0
Non rejection region = t =0
Rejection region = t != 0
t < 0, we reject H0 and conclude the current mean age of all CEOs of medium-sized companies in the United States is different from 58 years.
b. α = 0.01/2 = 0.005 , df = 70-1=69, critical value= 2.649
Non rejection region = [-2.649,2.649]
Rejection region = t 2.649
Work Step by Step
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