so the ice rink diameter is 80 feet what mean that the radius of ice rink is 40 feet
the walkway is 10 feet wide
so 10+40=50 what mean that the radius and the walkway wide make 50 feet length together
using this length area = pi*r^2 = 3,14*(50)^2 = 7850 feet squared
area of ice rink = 3,14*40^2 = 5024 feet squared
area of the walkway = 7850-5024 = 2826 feet squared
hope helped
