Question

You decide to test the claim that the mean Age of TCC students is less than 30 at the .05 significance level. From your sample of 89 students, the mean age was 27.4, with a standard deviation of 9.2 years. The alternative hypothesis is: The Test Statistic is: The P Value is:

Answer 1

this is the left tailed test .  

The null and alternative hypothesis is ,

H0 :   = 30

Ha : <30

Test statistic = z

= ( - ) / / n

= (27.4-30) / 9.2/ 89

z = -2.67

P(z <-2.67 ) = 0.0038

P-value = 0.0038