Answer:
15pi
Step-by-step explanation:
assuming the rounded shapes are semi-circles, we can determine each of their perimeters by the known formula for a full-circle, and divide by 2.
the perimeter of a circle with radius r, is 2×pi×r, hence, a semi-circle, is pi×r.
now we need to find r.
for the given side-length, we simply divide by 2, and we get 2.5 and 6.
for the missinf side-length, we use the Pythagorean formula - a²+b²=c², where a=5 and b=12, we get c=13. hence the third radius is 6.5.
now, the total perimeter will be:
2.5pi+6pi+6.5pi=15pi
