Question

A certain drug is used to treat asthma. In a clinical trial of the​ drug,

20

of

282

treated subjects experienced headaches​ (based on data from the​ manufacturer). The accompanying calculator display shows results from a test of the claim that less than

88​%

of treated subjects experienced headaches. Use the normal distribution as an approximation to the binomial distribution and assume a

0.01

significance level to complete parts​ (a) through​ (e) below.

Answer 1

Given : n=282 , x=20 , , ,

The sample proportion = p = x/n = 20/282 = 0.0709

Hypothesis : Vs

The test statistic is ,

Critical value : ; From normal probability integral table

Decision : Here ,

Therefore , reject the null hypothesis at 0.01 significance level

Conclusion : Hence , there is sufficient evidence to conclude that the less than 88% of treated subjects experienced headaches.