can someone help with 6 questions 1
Question 1
A sample of 81 account balances of a credit company showed an average balance of $1,200 with a standard deviation of $126.
- Formulate the hypotheses that can be used to determine whether the mean of all account balances is significantly different from $1,150.
- Compute the test statistic.
- Using the p-value approach, what is your conclusion? Let α = .05.
Question 2
During the recent primary elections, the democratic presidential candidate showed the following pre-election voter support in Alabama and Mississippi.
- We want to determine whether or not the proportions of voters favoring the Democratic candidate were the same in both states. Provide the hypotheses.
- Compute the test statistic.
- Determine the p-value; and at 95% confidence, test the above hypotheses.
Question 3
In order to estimate the difference between the yearly incomes of marketing managers in the East and West of the United States, the following information was gathered.
- Develop an interval estimate for the difference between the average yearly incomes of the marketing managers in the East and West. Use α = 0.05.
- At 95% confidence, use the p-value approach and test to determine if the average yearly income of marketing managers in the East is significantly different from the West.
- Using the ROI data set:
- For each of the 2 majors test the hypothesis at the 5% significance level:
- The mean ‘Cost’ for a college is $160,000. Be sure to interpret your results.
- For Business versus Engineering majors conduct a two sample test of the hypothesis at the 10% significance level (assume the variances are not equal):
- The average ’30-Year ROI’ for Business majors is less than for Engineering Majors. Be sure to interpret your results.
- For each of the 2 majors test the hypothesis at the 5% significance level: