The best evidence to show which class has had greater success on field day over the last 10 years is ''Mr. Roland’s class was more successful because his class’s lower quartile was the same as Mrs. Cai’s class’s upper quartile''.
Given
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.
What is the upper quartile?
The upper quartile is the median of the upper half of the data points.
The lower quartile is the median of the lower half of the data points.
From the given the value of the upper quartile of Mrs. Cai's class = 4 and the lower quartile of Mr. Roland’s class = 4.
So, Mrs. Cai's class's box ranges from 2 to 4, that is, her class’s upper quartile is 4.
Mr. Roland's class's box ranges from 4 to 7, that is, his class’s lower quartile 4.
Hence, the best evidence to show which class has had greater success on field day over the last 10 years is ''Mr. Roland’s class was more successful because his class’s lower quartile was the same as Mrs. Cai’s class’s upper quartile''.
To know more about Upper quartile click the link given below/
https://brainly.com/question/7039036