The mean is basically the average.
To find the mean we need to add up all the values and divide it by the amount of games he played.
82 + 83 + 65 + 84 + 76 = 390
390/5
Mean = 78
Do the area of the circle as a whole minus (72/360 x radius^2) and then minus the other grey area.
Answer:
Step-by-step explanation:
I set this up as an inequality,

. If you take the cubed root of 800, you get the lower bound of the side length, which is 9.2. Then I just worked my way up until I hit the first number that put me over a volume of 800. That number is 9.29, because 9.28 cubed is 799.1 (not high enough) and 9.29 cubed is 801.8. Therefore, the bounds of the sides exist within a conjunction:

. That's the best I could come up with to help on that one. Wasn't sure if there was another method you were taught at school. I just used common sense more than any rule.