# Chapter 9 Essay

30245 WordsJun 18, 2013121 Pages
Exam 1. 1. All continuous random variables are normally distributed. False. 2. The actual weight of hamburger patties is an example of a continuous random variable. True 3. The college of business administration at acorn University offers a major in finance. Based on historical records, 30% of the college of business students major in Finance. A random sample of 20 students is selected. What is the probability that exactly 3 of the selected students are majoring in Finance? .0716 4. Assume that we have selected a random sample of 25 units from a normally distributed large population. If u = 15, and c2=4, what is the probability that we will obtain a sample mean of less than 14? .0062 5. The normal approximation of the binomial distribution…show more content…
The level of confidence increases b. n decreases c. s increases d. All of the above Score: 4/4 Question 2 (4 points) In a manufacturing process a random sample of 9 bolts manufactured has a mean length of 3 inches with a variance of .09. What is the 90% confidence interval for the true mean length of the bolt? Student response: Percent Value 0.0% 0.0% 0.0% 100.0% 0.0% Correct Response Student Response Answer Choices a. 2.8355 to 3.1645 b. 2.5065 to 3.4935 c. 2.4420 to 3.5580 d. 2.8140 to 3.1860 e. 2.9442 to 3.0558 Score: 4/4 Question 3 (4 points) For the following hypothesis test where H0:  10 vs. Ha: > 10, we reject H0 at level of significance ? and conclude that the true mean is greater than 10 when the true mean is really 8. Based on this information we can state that we have: Student response: Percent Correct Student Answer Choices Value Response Response 100.0% 0.0% 0.0% 0.0% a. Made a Type I error b. Made a Type II error c. Made a correct decision d. Increased the power of the test Score: 4/4 Question 4 (4 points) The power of a statistical test is the probability of rejecting the null hypothesis when it is true. Student response: Percent Value 0.0% Correct Response Student Response Answer Choices a. True 100.0% b. False Score: 4/4 Question 5 (4