Positive proportion and inverse proportion are very important concepts in mathematics, which are widely used in the real world. Among them, positive proportion means that two quantities increase or decrease simultaneously with the increase of one of them; Inverse ratio means that the increase of one quantity leads to the decrease of another quantity, and their products remain unchanged. The sixth grade mathematics mainly studies the concepts and applications of positive proportion and inverse proportion.

First, direct ratio.

Positive proportion means that the relationship between two quantities is proportional, that is, when one quantity increases or decreases, the other quantity will also increase or decrease according to a certain proportion.

Second, the inverse ratio

Inverse proportion means that the relationship between two quantities is inverse proportion, that is, when one quantity increases, the other quantity will decrease according to a certain proportion, and their product remains unchanged.