MATH 215| Mathematics 215 Introduction to Statistics
Assignment 5 complete 2025 Athabasca University
Assignment 5
Overview
Total marks: / 70
This assignment covers content from Unit 5. It assesses your ability to use sampling distributions in
hypothesis testing about the difference between two or more population means or the difference between
two population proportions, including tests for experiments with more than two categories and tests about
contingency tables.
Instructions
• Show all your work and justify all of your answers and conclusions.
• Keep your work to 4 decimals, unless otherwise stated.
• Note: Finishing a test of hypotheses with a statement like “reject H0” or “do not reject H0” will be
insufficient for full marks. You must also provide a written concluding statement in the context of the
problem itself. For example, if you are testing hypotheses about the effectiveness of a medical
treatment, you must conclude with a statement like, “we can conclude that the treatment is effective” or
“we cannot conclude that the treatment is effective.”
(9 marks)
1. A researcher is interested in examining the cholesterol levels of heart-attack patients. Cholesterol levels
are measured for 28 heart-attack patients (2 days after their attacks) and 30 other hospital patients who
did not have a heart attack. The researcher believes that cholesterol levels will be higher for the heart-
attack patients. Random samples from each group provide the following results:
Heart-Attack Patients Non-Heart-Attack Patients
Sample Size 28 30
Mean Cholesterol (mg/DL) 213.9 193.1
Standard Deviation of Cholesterol (mg/DL) 47.7 22.3
Assume that the cholesterol levels for both populations are normally distributed and that the population
standard deviations are equal.
Using a 5% significance level, can the researcher conclude that the mean cholesterol level of heart-
attack patients is greater than the mean cholesterol level of non-heart-attack patients? Formulate and
test the appropriate hypotheses. State and explain your conclusion within the context of the question.
Use the critical value approach.
,
Assignment 5 complete 2025 Athabasca University
Assignment 5
Overview
Total marks: / 70
This assignment covers content from Unit 5. It assesses your ability to use sampling distributions in
hypothesis testing about the difference between two or more population means or the difference between
two population proportions, including tests for experiments with more than two categories and tests about
contingency tables.
Instructions
• Show all your work and justify all of your answers and conclusions.
• Keep your work to 4 decimals, unless otherwise stated.
• Note: Finishing a test of hypotheses with a statement like “reject H0” or “do not reject H0” will be
insufficient for full marks. You must also provide a written concluding statement in the context of the
problem itself. For example, if you are testing hypotheses about the effectiveness of a medical
treatment, you must conclude with a statement like, “we can conclude that the treatment is effective” or
“we cannot conclude that the treatment is effective.”
(9 marks)
1. A researcher is interested in examining the cholesterol levels of heart-attack patients. Cholesterol levels
are measured for 28 heart-attack patients (2 days after their attacks) and 30 other hospital patients who
did not have a heart attack. The researcher believes that cholesterol levels will be higher for the heart-
attack patients. Random samples from each group provide the following results:
Heart-Attack Patients Non-Heart-Attack Patients
Sample Size 28 30
Mean Cholesterol (mg/DL) 213.9 193.1
Standard Deviation of Cholesterol (mg/DL) 47.7 22.3
Assume that the cholesterol levels for both populations are normally distributed and that the population
standard deviations are equal.
Using a 5% significance level, can the researcher conclude that the mean cholesterol level of heart-
attack patients is greater than the mean cholesterol level of non-heart-attack patients? Formulate and
test the appropriate hypotheses. State and explain your conclusion within the context of the question.
Use the critical value approach.
,
