Question

According to the internet, the average (mean) height of adult men in the U.S. is 69.3 inches tall (about 5 foot, 9 inches tall). That seems wrong to me, and so I decide to test whether or not that is true by measuring the heights of a random sample of 63 adult men. I find that my sample of 63 women has a mean height of 71.2 inches, and a standard deviation of 1.2 inches.

Answer the following questions in the space provided below:

1. State the null and alternative hypotheses. (Type mu instead of using the symbol.)
2. Find the standard error of the distribution of sample statistics (null distribution). You will need to use one of the formulas for standard error from your formula sheet. Write down the formula you used and round the answer to one decimal place.
3. Find the t-score for our observed statistic for this example.
4. Formulate a conclusion based on your t-score.

Answer 1

Here claim is that mean is 69.3

So null hypothesis is and alternative hypothesis is

Standard error is

Test statistics is

P value is TDIST(12.57,62,2)=0.0000

As P value is less than alpha we reject the null hypothesis

Hence we do not have sufficient evidence to support the claim that mean is 69.3