- For the dot plot titled Class A:
- The number line ranges from 1 to 7 in increments of 1.
- The data for the dot plot are as follows:
- 1: 1 dot
- 2: 1 dot
- 3: 3 dots
- 4: 4 dots
- 5: 5 dots
- 6: 6 dots
- 7: 7 dots
- For the dot plot titled Class B:
- The number line ranges from 14 to 20 in increments of 1.
- The data for the dot plot are as follows:
- 14: 1 dot
- 15: 1 dot
- 16: 3 dots
- 17: 4 dots
- 18: 5 dots
- 19: 6 dots
- 20: 7 dots
Each of the dot plots shown represents the number of glue sticks brought in by each student for two classes, class A and class B. Which statement best compares the standard deviations of the numbers of glue sticks brought in by each student for these two classes?
Correct answer: B
Explanation
Choice B is correct. Standard deviation is a measure of the spread of a data set from its mean. The dot plot for class A and the dot plot for class B have the same shape. Thus, the frequency distributions for both class A and class B are the same. Since both class A and class B have the same frequency distribution of glue sticks brought in by each student, it follows that both class A and class B have the same spread of the number of glue sticks brought in by each student from their respective means. Therefore, the standard deviation of the number of glue sticks brought in by each student for class A is equal to the standard deviation of the number of glue sticks brought in by each student for class B.
Choice A is incorrect and may result from conceptual or calculation errors.
Choice C is incorrect and may result from conceptual or calculation errors.
Choice D is incorrect and may result from conceptual or calculation errors.
Loading…
Searched on YouTube by topic, not by question text. Open this search on YouTube →
SAT® and PSAT/NMSQT® are trademarks registered by the College Board, which is not affiliated with, does not sponsor, and does not endorse this project.