Answer:
a. 20 points
Step-by-step explanation:
Range = Largest given value - Smallest given value.
Identifying the range of test 1
Looking at the dot plot the lowest test grade appears to be 50 while the highest is 90.
So range of test 1 = 90 - 50 = 40
Identifying the range of test 2
Looking at the plot the lowest test grade appears to be 40 while the highest appears to be 100
So range = 100 - 40 = 60
Identifying the differences between the ranges
Test 1 range : 40
Test 2 range : 60
Difference between the two : 60 - 40 = 20 points
