Answer:
A) 2
Step-by-step explanation:
In a box-and-whisker plot, the left "whisker" is the bottom 25%, the line between the two "boxes" is to 50%, and the right "whisker" is the top 25%.
In class 2, the 90 point mark is where the line between the boxes are, which means that 50% of the class earned 90% or less. That is 13/2 = 6.5 people (this is impossible but it will work out)
In class 1, the 80 point mark is also where 50% is. So, half of the students, 17/2 = 8.5 people, have 80 points or less.
8.5 - 6.5 = 2 people.
