Hey there Javin!
The formula the we would use is
. . .

This would mean that we would just multiply what ever is the diameter.
So, in this case, this coin has the diameter of 22, we do

and that would give us 44. (but that is not the answer quite yet).
_____________________________________________________________
The formula of a Circle is

We now know that the diameter is 22.So this would mean that the radius is half of this, which is 11.
Plug int he number's in the formula, 3.14*11^2 ≈
379.94
Your correct answer would be
. . .

Hope this helps.
~Jurgen