N3E9p19

Problem 19:

Each of the diagrams above contains a square with a side length of 2 units.  The circles contained within each square are congruent (e.g., the 4 in the middle square each have a diameter of 1 unit.)

Which of the diagrams above has the greatest ratio of area of the circle(s) to the area of the square?  Show your work or justify your answer.