Because I cannot draw a picture in this problem, I will do my best to describe it in words. This problem is about a circular railway track. The diagram that goes with it shows one of the 15 curved pieces. Its width is MEASURED 1 cm and its arc length of the inner edge is MEASURED 30 cm. The circular model railway track is made by connecting the 15 identical pieces. When the 15 pieces are assembled, the circumference of the inner edge is 450 cm. The radius of the inner edge is 71.6 cm. So, the scale used in the DIAGRAM is 1:10. I don't understand why the scale for the diagram is 1:10. Can someone please explain?