Answer:
13
Explanation:
The easiest way to do this problem is to count the number of times he scored 19 or 20 points. He has scored 19 points 4 times and 20 points 3 times. That is 7 times he has been 19 or more.
So if you count the "exs" for 18 and below, you will get 20 - 7 = 13
The answer is 13