A decorative arrangement of floor tiles forms concentric circles, as shown in the figure to the right. The smallest circle has a radius of 2 feet, and each successive circle has a radius 2 feet longer. All the lines shown intersect at the center and form 12 congruent central angles. A random point inside the grid is selected. What is the probability that it lies in the shaded region?

wiskdls Apr 21, 2018