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 ...

1 China Academy of Safety Science and Technology, Beijing, China 2 State Key Laboratory of Fine Chemicals, Department of Chemical Machinery and Safety Engineering, Dalian University of Technology, ...