5/29/25, 8:19 AM Math 110 - Module 8 Exam
Math 110 - Module 8 Exam
Portage Learning
Question 1
Suppose we have independent random samples of size n1 = 420 and n2 = 510. The
proportions of success in the two samples are p1 = 0.38 and p2 = 0.43. Find the 99%
confidence interval for the difference in the two population proportions.
Answer the following:
1. Multiple choice: Which equation would you use to solve this problem?
2. List the values you would insert into that equation.
3. State the final answer to the problem.
Answer:
From table 6.1, we see that 99% confidence corresponds to z = 2.58.
Equation: Option B.
Interval: (-0.1333, -0.03326)
Question 2
In a certain hospital, nurses are required to constantly make rounds to check in on all
patients. The nursing supervisor checks the records of 70 day shift nurses and finds that they
complete an average of 30 rounds per shift with a standard deviation of 4.6 rounds. Records
for 84 night shift nurses show an average of 25 rounds with a standard deviation of 5.7.
1. Find the 90% confidence interval for estimating the difference in population means.
2. Can you be 90% confident that there is a difference in means?
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Math 110 - Module 8 Exam
Portage Learning
Question 1
Suppose we have independent random samples of size n1 = 420 and n2 = 510. The
proportions of success in the two samples are p1 = 0.38 and p2 = 0.43. Find the 99%
confidence interval for the difference in the two population proportions.
Answer the following:
1. Multiple choice: Which equation would you use to solve this problem?
2. List the values you would insert into that equation.
3. State the final answer to the problem.
Answer:
From table 6.1, we see that 99% confidence corresponds to z = 2.58.
Equation: Option B.
Interval: (-0.1333, -0.03326)
Question 2
In a certain hospital, nurses are required to constantly make rounds to check in on all
patients. The nursing supervisor checks the records of 70 day shift nurses and finds that they
complete an average of 30 rounds per shift with a standard deviation of 4.6 rounds. Records
for 84 night shift nurses show an average of 25 rounds with a standard deviation of 5.7.
1. Find the 90% confidence interval for estimating the difference in population means.
2. Can you be 90% confident that there is a difference in means?
file:///C:/Users/Hannie/Downloads/SERVER.HTML 1/3
