Didactic material “Math rods”

Ten rods identical with the Red Rods in length, but divided into red and blue sections. The shortest rod is red. The second is twice the size of the first; one half is painted red and the other half is blue. The third rd is three times the size of the first and is divided into three sections; the first painted red, the second is blue, and the third red. All the other rods are divided in a similar fashion, alternating red and blue, the first section always being red.