Question 152990
Test the hypothesis that the average age of the students in the following group is 35. 



Student # Age
1............ 37
2............ 43
3............ 22
4............ 36
5............ 35
6............ 28
7............ 44
8............ 33
9............ 26
10........... 36
11........... 21
12............ 53
13............ 38
14............ 44
15............ 31 

Develop a problem statement 
What is the average age of the students in the following group?
Add the ages and divide by 15 to get 35.133333
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Create the hypothesis, null and alternate based on the problem statement 
Decide on one- or two-tailed test 
Ho: u = 35
Ha: u is not equal to 35
Two-tailed test because Ha is "not equal to".
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Develop the decision criteria, significance level, and critical value (if the P-value is not used)
Let alpha = 5%; then the critical values with df of 14 are t = +/- 2.145 
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Calculate the test statistic:
t(35.133333..) = (35.133333 - 35)/[8.78016/sqrt(15)] = 0.058814...
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What is the decision of the null hypothesis? 
Since the test statistic does not fall in the rejection interval,
fail to reject Ho.
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Cheers,
Stan H.