Easy. 8 hats because no one likes hats anymore.
definition is valid since center is exactly 1radius away from any point on the outersurface.
other figures do not fit this defn
The mean/average is found by adding all of your values and then dividing by the number of values found.
7+7+7+7+7+7+7+7+7+7=70
There are 10 size 7 shoes. Divide 70 by 10 to get the mean, which is 7.
Another ex.
Find the average of numbers listed
1+4+8
these add up to 13
there are 3 numbers listed
13/3=4.33 so the mean is 4.33
95 meals per night and theres 7 nights 95x7 = 665