The relationship between the intensity of sound, and the distance from the source of the sound, is `I = k/d^2`, where `I` is the intensity of sound measured in watts per square metre (W/m^{2}), `d` is the distance in metres from the source, and `k` is a constant.

The intensity of sound is `20` W/m^{2} at a distance of `50` m from the source.

A graph showing the relationship between intensity of sound and distance from the source is