INSTRUCTOR ANSWER GUIDE
OpenStax Introductory Business Statistics 2e
Instructor Answer Guide
,OpenStax Introductory Business Statistics 2e
Instructor Answer Guide
CHAPTER 7: THE CENTRAL LIMIT THEOREM
Exercise 1. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
a. What is the distribution for the weights of one 25-pound lifting weight? What is
the mean and standard deviation?
b. What is the distribution for the mean weight of 100 25-pound lifting weights?
c. Find the probability that the mean actual weight for the 100 weights is less than
24.9.
Solution a. U(24, 26), 25, 0.5774
b. N(25, 0.0577)
c. 0.0416
Exercise 2. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Draw the graph from Exercise 7.1.
Solution
Exercise 3. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Find the probability that the mean actual weight for the 100 weights is greater
than 25.2.
Solution 0.0003
Exercise 4. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Draw the graph from Exercise 7.3.
2
October 28, 2025
, OpenStax Introductory Business Statistics 2e
Instructor Answer and Solution Guide
Chapter 7: The Central Limit Theory
Solution
Exercise 5. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Find the 90th percentile for the mean weight for the 100 weights.
Solution 25.07
Exercise 6. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Draw the graph from Exercise 7.5.
Solution
Exercise 7. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
a. What is the distribution for the sum of the weights of 100 25-pound lifting
weights?
b. Find P(Σx < 2,450).
Solution a. N(2,500, 5.7735)
b. 0
Exercise 8. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Draw the graph from Exercise 7.7.
3
October 28, 2025
OpenStax Introductory Business Statistics 2e
Instructor Answer Guide
,OpenStax Introductory Business Statistics 2e
Instructor Answer Guide
CHAPTER 7: THE CENTRAL LIMIT THEOREM
Exercise 1. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
a. What is the distribution for the weights of one 25-pound lifting weight? What is
the mean and standard deviation?
b. What is the distribution for the mean weight of 100 25-pound lifting weights?
c. Find the probability that the mean actual weight for the 100 weights is less than
24.9.
Solution a. U(24, 26), 25, 0.5774
b. N(25, 0.0577)
c. 0.0416
Exercise 2. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Draw the graph from Exercise 7.1.
Solution
Exercise 3. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Find the probability that the mean actual weight for the 100 weights is greater
than 25.2.
Solution 0.0003
Exercise 4. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Draw the graph from Exercise 7.3.
2
October 28, 2025
, OpenStax Introductory Business Statistics 2e
Instructor Answer and Solution Guide
Chapter 7: The Central Limit Theory
Solution
Exercise 5. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Find the 90th percentile for the mean weight for the 100 weights.
Solution 25.07
Exercise 6. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Draw the graph from Exercise 7.5.
Solution
Exercise 7. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
a. What is the distribution for the sum of the weights of 100 25-pound lifting
weights?
b. Find P(Σx < 2,450).
Solution a. N(2,500, 5.7735)
b. 0
Exercise 8. A manufacturer produces 25-pound lifting weights. The lowest actual weight is 24
pounds, and the highest is 26 pounds. Each weight is equally likely so the
distribution of weights is uniform. A sample of 100 weights is taken.
Draw the graph from Exercise 7.7.
3
October 28, 2025
