Question

ATTN: This is my second time having to post this question. This is a multi-part question consisting of 2 parts: part A, consisting of 5 sub-sections and part B, consisting of 3 sub-sections. Both parts and all sub-sections are dependent upon the same data, making this one multi-part question. Chegg policy states that multiple questions within one post are not allowed however, questions with multiple sub-parts are allowed. Since this is only one question with multiple sub-parts, given that part B is dependent on part A, please answer all parts. Thank you.

A) An ACME Bearings manager wants to compare the average ball bearing
sizes from two different machines. She suspects the mean diameter for
bearings from machine 2 exceeds that of bearings from machine 1. She
takes two independent, random samples of size 50, one from each
machine. The mean and standard deviation of bearings taken from
machine 1 are 3.302 mm and 0.051 mm. The mean and standard deviation
of bearings taken from machine 2 are 3.355 mm and 0.050 mm. Run a
hypothesis test consistent with her suspicions. Be sure to
a. check all necessary assumptions;
b. state the null and alternative hypotheses;
c. decide whether or not to pool and explain why;
d. calculate the test statistic and p-value;
e. state your conclusion in a complete sentence based on the p-value.

B) Use the data from the previous problem to make a 98% t-interval for the
difference between the true means. In doing so, be sure to
a. check all necessary assumptions for making the t-interval;
b. calculate the interval endpoints;
c. interpret the interval in a complete sentence.

Answer 1