Perimeter Problem

Let A, B, and C be the centers of the three circles.

The distance from A to B is a straight-line distance that included the radius of the circle A and the radius of the circle B; thus, it will be 10 cm long. So will the distances from A to C and B to C, for a total distance of 30 cm.

These distances, from A to B, B to C, and C to A, are the same lengths as the lengths of the straps which are not touching the circles.

Now for the distances that wrap around the circles: for circle A, the straps wraps around 1/3 of the pipe, so its length will be 1/3 of the circumference of the circle:  (1/3)(2·π·r)  =  (1/3)(2·π·5)  =  (1/3)(10π).

Similarly for wrapping around circles B and C. (1/3)(10π) + (1/3)(10π) + (1/3)(10π)  =  10π

Total length for each:  (10π + 30) cm

Total for both:  (20π + 60) cm

[For each, the length will be one circumference of a circle plus three diameters.]

Well, both straps are the same size! Lucky you.

This is an iffy question for me so may be wrong although i will have a go at it.

I'm going to say you need 1/3 of one circle x3 [So basically the circumference of the circle) and guess rx3

C = 2πxr

so C = 2xπx5 which is C = 31.4159265358979324

remember C = Circumference so 31.4159265358979324

5x3 = 15

15 + 31.4159265358979324 = 46.4159265358979324cm

Probably wrong however so wait for a better answer.