As shown in the figure below, eight circles with radius 4cm each are lined in touch with the next circle.
When the center of each circle is connected by the line, find the area of the shaded area.
Pi is assumed to be 3.14.
The total of the interior angles of the octagon is 180 × (8 - 2) = 1080 = 360 × 3.
Thus the area to be found is 4 × 4 × 3.14 × 3 = 150.72 cm2.
