Re: Statistics - Sample Mean

how did you generate this? Do you have a program of some sort? It seems unlikely to me that you typed all this in by hand including all the items the problem doesn't ask for.

a) is correct

b) all your numbers are correct which is to be expected for software.

so yeah, you're ready to go to (c)

Re: Statistics - Sample Mean

I used the program, Minitab, to help me solve the problem. I was just wondering if it seemed to be correct.

Re: Statistics - Sample Mean

For part c, I'm wondering if I am wording this correctly.

In part a, I got the P(-2.5 < z < 2.5) = 0.9876, meaning that there is a high probability that the sample mean will be within 0.0075 the metal lathe's mean diameter. Then from part b, I got the mean, variance, standard deviation, and range and those values helped support my assumption in part a that P(-2.5 < z < 2.5) = 0.9876.

So, for part c, would it be wrong for me to say that I believe that the metal lathe is properly adjusted?

Re: Statistics - Sample Mean

Quote:

Originally Posted by

**AwesomeHedgehog** For part c, I'm wondering if I am wording this correctly.

In part a, I got the P(-2.5 < z < 2.5) = 0.9876, meaning that there is a high probability that the sample mean will be within 0.0075 the metal lathe's mean diameter. Then from part b, I got the mean, variance, standard deviation, and range and those values helped support my assumption in part a that P(-2.5 < z < 2.5) = 0.9876.

So, for part c, would it be wrong for me to say that I believe that the metal lathe is properly adjusted?

It's been ages since I looked at this but I'd guess this is a hypothesis test question.

H0: The lathe is properly adjusted

H1: The lathe is improperly adjusted

There must be something in your text that describes how to use these statistics to test one hypothesis vs. the other

Re: Statistics - Sample Mean

Honestly, I looked at the book and for the Chapters that this assignment is covering, there is nothing about that in the book. Plus my teacher never went over anything like this in class. So, for part c, I just wrote down what I believed, tried to use logic based on parts (a) and (b). Hopefully I am correct.