Question

A certain drug is used to treat asthma. In a clinical trial of the​ drug, 20 of 262 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 12% of treated subjects experienced headaches. Use the normal distribution as an approximation to the binomial distribution and assume a 0.05 significance level to complete parts​ (a) through​ (e) below.

A. Is the test two-tailed, left-tailed, or right-tailed?

B. What is the test statistic?

Z=[ ] (Round to TWO decimal places as needed)

C. What is the P-value?

P-value= [ ]    (Round to FOUR decimal places as needed)

D. What is the null hypotheses, and what do you conclude about it?

   Decide weather to reject the null hypothesis.

E. What is the final conclusion?

Answer 1

A)

left-tailed

B)

test statistic Z =-2.18

C)

p value =0.0146

D)

reject the null hypothesis.

E)Conclude that less than 12% of treated subjects experienced headaches.