Help me find the test statistic please!

Question

Consider a drug testing company that provides a test for marijuana usage. Among 266 tested​ subjects, results from 29 subjects were wrong​ (either a false positive or a false​ negative). Use a

0.10 significance level to test the claim that less than 10 percent of the test results are wrong.

Answer 1

Hi Britany,

I would use a Z test for proportions with n=266, phat=29/266=.109 qhat=1-.109=.891 and SE =(phat*qhat/n)^1/2 the the test statistic would be Z=(phat-.1)/SE, Use a 2 sided Z test with Xcrit=1.96

Jim