Problem: square a has an area of 81 square centimeters . square b has a perimeter of 32 centimeters . if square b is placed within square a and a random point is chosen within square a , what is the probability the point is not within square b ? 
Options: ['a ) 17 / 64', 'b ) 17 / 81', 'c ) 16 / 25', 'd ) 3 / 5', 'e ) 6 / 25']
b