Question 218363
Researchers were studying the relationship between age and pocket depth. They measured the pocket depth of 11 young subjects (ages 20-25) and 11 old subjects (ages 50-55). They wanted to know if there was a difference in mean pocket depth between the two groups. Assume that pocket depth has a relatively normal distribution. 
Name the appropriate test,
2-sample Ttest
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state the null and alternative hypotheses
Ho: u1 - u2 = 0
H1: u1 - u2 is not 0
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What assumption would need to be made for this test?
I'll leave that to you.
Cheers,
Stan H.