Question

A kindergarten teacher claims the average weight of a healthy student should be 42 pounds. A sample of 50 kindergartners has an average weight of 44 pounds. The population standard deviation is 5 pounds. At α = 0.05, does the data determine whether the average weight of a kindergartner is more than 42 pounds?

a) State the Hypotheses

b) Calculate the Test Statistic

Answer 1

Solution :

This is the right tailed test,  

a) The null and alternative hypothesis is ,

H₀ :   = 42

H_a : > 42

b) Test statistic = z =

= ( - ) / / n

= (44 - 42) / 5 / 50

Test statistic = z = 2.83