Lucy Baker is analyzing demographic characteristics of two television programs,American Idol (population 1)and 60 Minutes (population 2). Previous studies indicate no difference in the ages of the two audiences. (The mean age of each audience is the same.) Her staff randomly selected 100 people from each audience,and reported the following: ₁ = 43 years and ₂ = 45 years. Assume that $\sigma$₁ = 5 and $\sigma$₂ = 8. With a two-tail test and $\alpha$ = .05,the critical z values are _________________. A) -1.64 and 1.64 B) -1.96 and 1.96 C) -2.33 and 2.33 D) -2.58 and 2.58 E) -2.97 and 2.97

Question

Quizplus · Accepted Answer

Since we are conducting a two-tail test with a significance level of .05, we need to divide the significance level by 2 to calculate each tail's critical value. Using a standard normal distribution table or a calculator, we can find that the critical z-value for the left tail is -1.96 and the critical z-value for the right tail is 1.96. Therefore, the correct answer is B: -1.96 and 1.96.

Lucy Baker Is Analyzing Demographic Characteristics of Two Television Programs,American σ\sigmaσ

Lucy Baker Is Analyzing Demographic Characteristics of Two Television Programs,American $\sigma$