Exam 2
Exam 2
PUBH 600
Guidelines: You may use all of the resources (e.g., textbook, other books, websites) available to you, EXCEPT FOR OTHER PEOPLE. Your work must be done individually. Any exams that appear similar in format and/or answers will be considered to have been done in a group setting. All such exams will receive a score of 0. Late exams will not be accepted for any reason. Any late exams will receive a score of 0. These policies will be strictly enforced.
Remember that your exam must be typed in a Word document. Do not save your work as Word 2007. The exam can either be submitted as an attachment through WebCT or a hardcopy can be submitted to me in my office before 5:00 pm on November 20. Completed exams will be accepted at any time until the deadline.
Each question is worth 10 points.
1. Suppose the distribution of serum cholesterol values in undergraduate men is approximately normal with mean ( = 190 mg/dl and standard deviation ( = 40 mg/dl. a. What is the probability of selecting someone at random from this population who has a cholesterol value that is less than 180?
[pic]
b. You take a simple random sample of n = 49 individuals from this population and calculate the mean cholesterol of the sample. Describe the sampling distribution of xbar.
The standard deviation of the sampling distribution of x-bar is called the SE and is = [pic]
c. Regarding the mean derived from a sample of n = 49, what is the probability of getting a sample mean that is less than 180? [Determine Pr(xbar < 180)].
[pic]
2. Based on prior studies, a dental researcher is willing to assume that the standard deviation of the weekly sugar consumption in children in a particular community is 100 grams. How large a sample is needed to estimate mean sugar consumption in the community with a margin of error 10 grams at 95%?
[pic]
3. Based on prior studies, a
PUBH 600
Guidelines: You may use all of the resources (e.g., textbook, other books, websites) available to you, EXCEPT FOR OTHER PEOPLE. Your work must be done individually. Any exams that appear similar in format and/or answers will be considered to have been done in a group setting. All such exams will receive a score of 0. Late exams will not be accepted for any reason. Any late exams will receive a score of 0. These policies will be strictly enforced.
Remember that your exam must be typed in a Word document. Do not save your work as Word 2007. The exam can either be submitted as an attachment through WebCT or a hardcopy can be submitted to me in my office before 5:00 pm on November 20. Completed exams will be accepted at any time until the deadline.
Each question is worth 10 points.
1. Suppose the distribution of serum cholesterol values in undergraduate men is approximately normal with mean ( = 190 mg/dl and standard deviation ( = 40 mg/dl. a. What is the probability of selecting someone at random from this population who has a cholesterol value that is less than 180?
[pic]
b. You take a simple random sample of n = 49 individuals from this population and calculate the mean cholesterol of the sample. Describe the sampling distribution of xbar.
The standard deviation of the sampling distribution of x-bar is called the SE and is = [pic]
c. Regarding the mean derived from a sample of n = 49, what is the probability of getting a sample mean that is less than 180? [Determine Pr(xbar < 180)].
[pic]
2. Based on prior studies, a dental researcher is willing to assume that the standard deviation of the weekly sugar consumption in children in a particular community is 100 grams. How large a sample is needed to estimate mean sugar consumption in the community with a margin of error 10 grams at 95%?
[pic]
3. Based on prior studies, a