Part One: Z-Test for Comparing Two Means with UNEQUAL Variances

1. The IRS wants to learn if the values of IRA accounts of employees from two different firms are the same. It takes a random sample of 31 accounts from the first firm and 41 accounts from the second. The means in thousands of dollars are 35.7 for the first firm and 31.9 for the second, with standard deviations of 8.6 and 6.1 respectively. The IRS runs a simple test and finds the population variances are not equal. Assuming normal distributions, determine if the value of the accounts is the same at a significance level of 0.01. Find the p-value and determine the confidence interval.

Part Two: Z-Test for Comparing Two Proportions

1. An editor wonders if educational levels influence subscriptions to her magazine. She

commissions a poll which finds 256 of 640 college graduates polled and 336 of 960 high

school graduates polled subscribes to the magazine. Test at a level of significance of 0.05

if educational levels make a difference. Find the p-value, and determine the confidence

interval.

NEED GRAPHS AND STEP BY STEP