SCENARIO 12-1 a Corporation Randomly Selects 150 Salespeople and Finds $66 \%$

SCENARIO 12-1 A corporation randomly selects 150 salespeople and finds that $66 \%$ who have never taken a selfimprovement course would like such a course. The firm did a similar study 10 years ago in which $60 \%$ of a random sample of 160 salespeople wanted a self-improvement course. The groups are assumed to be independent random samples. Let $\pi _ { 1 }$ and $\pi _ { 2 }$ represent the true proportion of workers who would like to attend a self-improvement course in the recent study and the past study, respectively.
-Referring to Scenario 12-1, what is the critical value when performing a chi-square test on whether the population proportions are different if α = 0.05? a) $\pm 1.645$
b) $\pm 1.96$
c) $3.841$
d) $2.706$