Question

The test statistic of z=−3.11 is obtained when testing the claim that p <0.72.

a. Using a significance level of alpha=0.01​, find the critical​ value(s).

b. Should we reject H0 or should we fail to reject H0​ and is the evidence insufficient or sufficient?

Answer 1

Solution :

This is the LEFT tailed test .

The null and alternative hypothesis is

H0 : p =0.72

Ha : p < 0.72

Test statistic = z =-3.11

A

Z = Z0.01 = -2.33 ( Using z table )

B

Z <Z

Reject the null hypothesis .