The four circles in the figure below each have a radius of 5 units. The centers of each circle form a square. If you use 3.14 as the approximate ratio of a circle’s circumference to its diameter, what is the area of the interior [yellow] black star region?
Source: mathcontest.olemiss.edu 9/25/2006
Area of interior black star region = Area of square Area of 4 circle quarters.
= Area of square Area of 1 circle
Answer: square units.