Question

The box plot compares the number of events that Mrs. Cai’s and Mr. Roland’s classes won over the last 10 years on the school’s field day.

A number line goes from 0 to 10. Mrs. Cai's class's whiskers range from 0 to 8, and the box ranges from 2 to 4. A line divides the box at 3. Mr. Roland's class's whiskers range from 1 to 8, and the box ranges from 4 to 7. A line divides the box at 5.
Based on the data in the box plots, what is the best evidence to show which class has had greater success on field day over the last 10 years?

Mrs. Cai’s class was more successful because her interquartile range was less spread out.
Mrs. Cai’s class was more successful because she had the greater total spread.
Mr. Roland’s class was more successful because his class always won at least one event.
Mr. Roland’s class was more successful because his class’s lower quartile was the same as Mrs. Cai’s class’s upper quartile.

Answer 1

Answer: Mr. Roland’s class was more successful because his class’s lower quartile was the same as Mrs. Cai’s class’s upper quartile.

Explanation: Roland’s box (Q1–Q3 = 4–7) is shifted to the right of Cai’s box (2–4) and his median is higher (5 vs. 3). In particular, Roland’s Q1 = 4 equals Cai’s Q3 = 4, showing Roland’s typical results are generally higher than Cai’s.