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Population Mean to a
Problem: Compare the mean age of incoming students to the known mean age for all previous incoming students. A random sample of 30 incoming college freshmen revealed the following statistics: mean age 19.5 years, standard deviation 1 year. The college database shows the mean age for previous incoming students was 18.
State the Hypothesis
Ha: There is a significant difference between the mean age of past college students and the mean age of current incoming college students.
Degrees of Freedom = n-1 or 29
Critical value from t-distribution = 2.045
If the results had not been significant, the null hypothesis would not have been rejected. This would be interpreted as the following: There is insufficient evidence to conclude there is a statistically significant difference in the ages of current and past freshman students.