NCERT Solutions for Class 8 maths Chapter 13 Direct and Inverse Proportions

In the direct variation, as one number increases, so does the other. It is also called direct proportion: they're the same thing. An example of this is the relationship between age and height. In an inverse variation, it's precisely the opposite: as one number increases, the other decreases. A direct and inverse proportion are used to show how the quantities and amount are related to each other. A proportion states that two ratios like a/b and c/d are equal to each other, in such a way, a/b = c/d.