https://i.postimg.cc/4dQY9Lbs/IMG-8573-1.jpg https://i.postimg.cc/cHFsWVBg/IMG-8574-1.jpg
P(Moon Hit) = Area of Moon / Area of Cover
{ 2 1/2 = 2.5 }
Area of Moon = pi (diameter/ 2)^2 = pi (2.5/2)^2 = pi (1.25)^2 = 4.9 in ^2
Area of Cover = (5 1/2) ( 8 1/2) = (5.5) (8.5) = 46.75 in^2
So
4.9 / 46.75 ≈ .1048 ≈ 10.5%