When the pressure of a gas is increased, while maintaining a constant temperature, the volume of the gas decreases. What is the relation between pressure and volume of the gas?
Inverse
When the temperature is constant, an increase in pressure results in a decrease in volume.
Hence, they are inversely related.
Now, they will be inversely proportional if PV = constant
Note: Boyle's law states that when the temperature is kept constant, PV = constant. Or in other words, Pressure is inversely proportional to the volume of the gas.