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For the fallowing question, we need to assume that the sample standard deviation is 16. We need to check to see if the sample average weight of 177 is statistically larger than the standard weight of 170. We are asked to you the usual 5 step procedure.

Question: The following weights were obtained from a randomly selected sample of 20-year-old, 6-foot-1 inch males from Minnesota. This sample of 25 males had a mean weight of 177 lb. Based on this sample, are Minnesota males heavier than males in general? The mean weight of all US males (6'1'') is 170**lb, and the population **standard deviation is 16. Assume a normal distribution. Use alpha= 0.05.

So, our n= 25, sd= 16, and y^bar= 177 (?)

I know it most likely seems a very easy t-test, however, I would appreciate your help. I have an issue organizing the steps of this problem, and starting to solve this problem: is Ho=177 and Ha not = 177?

Thank you for your help!

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The claim you are testing is "Minnesota males [are] heavier than males in general". How would you write that as a hypothesis? – tabstop Feb 20 '14 at 4:53
Hypothesis would be: Minnesota males are the same weight as the males in general. So, Ho: μ = 170 (?) and then Ha: μ > 170 (?) – juknee Feb 20 '14 at 4:59
You definitely need $\mu > 170$ as your claim, since there's no other way to express "weighs more" than to use "more". Your textbook conventions will determine whether the other hypothesis is $=170$ or $\leq 170$. – tabstop Feb 20 '14 at 5:00
@tabstop: so wait, the Ho would be, Ho: μ=170lb; the average weight of men is 170. ? – juknee Feb 20 '14 at 22:58
@tabstop: I just edited my post. Does my work looks correct? thank you! – juknee Feb 20 '14 at 23:07

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