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In: Statistics and Probability

Question 3 At a local university, a sample of 64 evening students was selected in order...

Question 3

At a local university, a sample of 64 evening students was selected in order to determine whether the average age of the evening students is significantly different from 21. The average age of the students in the sample was 23 years. The population standard deviation is known to be 4.5 years. Determine whether or not the average age of the evening students is significantly different from 21. Use a 0.05 level of significance

Expert Solution

Solution :

The null and alternative hypothesis is ,

H0 : = 21

Ha : 21

Test statistic = z

= ( - ) / / n

= (23 - 21) / 4.5 / 64

Test statistic = 3.56

P-value = 0.0004

= 0.05

P-value <

Reject the null hypothesis .

There is sufficient evidence to determine whether the average age of the evening students is significantly different from 21.

orchestra answered 2 years ago

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