To solve this problem, you add all the numbers together and divide by the total amount of things. In this case, there are six scores, 210, 195, 213, 201, 226, and 155. You would add all of these things together, and then divide by six. All of these things added together equals 1,200. This divided by 6 is 200. David's average score would be a. 200. Hope this helps!