Inverse proportion is the relationship between two variables when their product is equal to a constant value. When the value of one variable increases, the other decreases, so their product is unchanged.
y is inversely proportional to x when the equation takes the form:
y = k/x
or
xy = k
where k is a constant
In contrast, directly proportional variables increase or decrease with each other.
Inversely Proportional Examples
- Speed and travel time are inversely proportional. The faster you go, the less time it takes to complete your trip.
- The volume of an ideal gas is inversely proportional to the pressure of the gas (Boyle's Law)