To find the mean of a group of data, you add up all of the numbers and divide the total by the amount of numbers there are. In this case, you have 15,11,10,11,14,10,15,10,and 12.
It would be at 2. Here is why: -2 and 4 are 6 places away from each other. Now divide that by 3 (for the thirds). so each third is 2. Now thirds 2will be four, so add that to -2 and you get 2.
