Proportion

In this Math video tutorial on Ratio and Proportion we look into the field of Proportion and cover the following points: What is proportion? What is the difference between proportion and ratio? What is the difference between proportion and rate? What are the names of the outer and inner terms of a proportion? How many types of proportion are there? What is the difference between them? How do you express a direct proportion graphically? How do you express an inverse (indirect) proportion graphically? What is the graph shape for direct/indirect proportion? Why?