Answer:
72.52
Explanation:
circumference of a circle formula =
where r is the radius
the radius is half of diameter, and the diameters for all semicircles are given.
so the radius for the smaller semicircles is 10/2 which is 5
so
= 2(3.14)(5) = 31.4
31.4 is the circumference of the whole circle, since we have 2 semicircles with the same radius, we don't need to divide this by 2, we will simply use 31.4 for instead of doing this exact calculation again for the other small semicircle.
for the larger cemicircle, the diameter is 16 so the radius will be 16/2 which is 8
= 2(3.14)(8) = 50.24
since 50.24 is the circumference of an entire circle, we will have to divide this by 2 to d=find the circumference of the semicircle.
50.24/2 = 25.12
Now we will simply add up the lengths of the borders,
31.4 + 25.12 + 16 = 72.52