Proportional ratio: two variables that satisfy the relationship y/x=k(k is a constant). We call the relationship between these two variables proportional.

Obviously, if y is proportional to x, then y/x=k(k is a constant); or vice versa, Dallas to the auditorium

For example, if the speed is constant, the distance is proportional to the time; In engineering problems, if the work efficiency remains unchanged, the total amount of work is directly proportional to the working time.

Note: k cannot be equal to 0.

Inverse ratio:

Two variables that satisfy the relationship xy=k or y=k/x(k is a constant), we say that these two variables are inversely proportional;

Obviously, if y is inversely proportional to x, xy=k(k is a constant); or vice versa, Dallas to the auditorium

For example, if the distance is constant, the speed is inversely proportional to the time; In the work problem, if the total amount of work is fixed, the work efficiency is inversely proportional to the working time.

That is to say, if the total amount remains unchanged, other quantities will change, and other quantities will be inversely proportional.