Why is the approximate perimeter of a semi circle with a radius of 8 m?

Hello:

the perimeter of a circle is : P=2πr r : radius r = 8m

P = 2*3.14*8 = 50.24

the approximate perimeter of a semi circle with a radius of 8 m is : P/2 = 25.12m

Circumference of a circle with radius 8 =

c = 2 pi 8

For semi circle we will divide this by 2 and then add the base segment which is the length of the radius * 2.

p = (2 * 3.14 * 8) / 2 + 16

perimeter = 41.12 m