Question

The director of research and development is testing a new drug. She wants to know if there is evidence at the 0.05 level of significance that the drugs stays in the system for more than 329 minutes. For a sample of 38 patients, the mean time the drug stayed in the system was 334 minutes. Assume the population standard deviation is 22.

Find P-value (round four decimals) and Conclusion (Reject or fail to reject)

Answer 1

Solution :

This is the right tailed test,  

The null and alternative hypothesis is ,

H0 :   = 329

Ha : > 329

Test statistic = z =

= ( - ) / / n

= (334 - 329) / 22 / 38

Test statistic = z = 1.40

P(Z > 1.40) = 1-P (Z < 1.40) = 1 - 0.9192

P-value = 0.0808

= 0.05  

P-value >

Fail to reject the null hypothesis .