In order to solve this, you have to take the number of copies of the Prisoner of Azkaban and divide it by the number of copies of the Sorcerer's Stone:
13.2÷20=0.66
To get this into a percentage, multiply the 0.66 by 100, and get 66%, meaning that The Prisoner of Azkaban was sold only 66% as much as The Sorcerer's Stone.
Answer:
I just had this problem on a test! I hope this helps, i will attach a picture of my messy work, but hopefully that will give you an idea on how do do it!
How to Solve!-
Repeat this distance formula for each side
65 x .12 = 7.865 - 7.8 = 57.2
Tree 3 diagram is the answer
