Inverse proportionality is when two magnitudes increase, the other decreases in the same proportion, and when the first decreases, the second increases in the same proportion. Proportionality is the conformity or proportion (equality of two reasons) of some parts with the whole or of elements linked to each other, or more formally, it turns out to be the relationship between measurable quantities.
The constant of inverse proportionality is obtained by multiplying the quantities with each other.
In the case that the independent and dependent variables are proportional, that is, when the independent variable increases and the dependent variable does so to the same extent, and when the dependent variable decreases, the independent variable increases to the same extent, at that time the function that relates them is inverse proportionality.
Two quantities are inversely proportional if when multiplying (or dividing) one of them by a number, the other is divided (or multiplied) by the same number.
For example: The faster the car, the less time it will take to go around the circuit. Imagine that taking a circuit of around 100 km / h, the car takes 12 minutes. In this case and knowing that there is an inverse proportionality relationship we can say that if we multiply the speed by 2 (200 km / h), then the time per lap will be divided by 2 (6 min).
If, on the other hand, you reduce your speed by half (100 km / h: 2 = 50 km / h) the time per lap would be double (12 min x 2 = 24 min)
If the car had its last lap in 4 minutes, what would have happened to the speed of the car during that lap?
(12 min: 4 min = 3) Since the time has been divided by 3, the speed must be multiplied by 3 (3 x 100 km / h = 300 km / h). That is, the speed at which the car made its last lap was 300 km / h.
With these examples we can see why the name INVERSE for this type of proportionality relationship. What happens with one of the magnitudes happens in an INVERSE way with the other magnitude, when one increases, the other decreases and vice versa.
