Let me take the proportion as an example.
For example, y=2+x, and the larger x is.
The bigger y is, the smaller x is and the smaller y is, but they are not directly proportional.
The proportional relationship must be multiplied, for example, y=2x.
Moreover, it can be seen from the image of the function that the proportional function must pass through the origin, and its intercept with the coordinate axis is zero, which means that there is no addition or subtraction of factors in the analytical formula.
Simply put:
a∝b
Proportional
It means that the bigger A is, the bigger B is.
a∝ 1/b
be in reverse ratio
It means that the bigger A is, the bigger 1/b is, that is, the smaller B.