These are decimal numbers, and dots above some of the digits make them recurring decimals. One dot means the digit under it repeats infinitely. In other words, it goes on forever (and ever and ever).

A ratio compares two or more quantities by using parts of a whole. In this bracelet, there are 2 parts red compared to 3 parts blue. The ratio of red beads to blue beads is 2 : 3. This is said aloud ...