Answer:
B. 2
To find MAD, find the mean of the set, then find how far each number is from the mean. Next, find the mean of THAT set of numbers. Yea, I know it's a bit confusing... don't worry!
Find the mean of the set:
12 + 10 + 10 + 8 + 6 + 7 + 7 + 12
72
72 / 8
9
Find how far each number is from 9:
12 - 9 = 3
10 - 9 = 1
10 - 9 = 1
9 - 8 = 1
9 - 6 = 3
9 - 7 = 2
9 - 7 = 2
12 - 9 = 3
Find the mean of that number set:
{3, 1, 1, 1, 3, 2, 2, 3}
3 + 1 + 1 + 1 + 3 + 2 + 2 + 3
16
16 / 8
2
So the answer is 2!
Not so hard after all :D