Find critical value and critical region.

Question

A 0.05 significance level is used for a hypothesis test of the claim that when parents use a particular method of gender​ selection, the proportion of baby girls is less than 0.5. Assume that sample data consists of 45 girls in 100 ​births, so the sample statistic of 9/20 results in a z score that is 1 standard deviation below 0. Complete parts​ (a) through​ (h) below.

g. What are the critical​ value(s)?

h. What is the area of the critical​ region?

Answer 1

The critical value for a left-tailed test with 0.05 level of significance is -1.645 (the z-score corresponding to a left-tailed area of 0.05)

The area of the critical region is the level of significance = 0.05