The intensity of electric field from a certain point that is assumed is proportional inversely to the square of distance’s magnitude from source. As one can see the electric field intensity is proportional inversely. Then the increase in magnitude of the space between source charge the electric field intensity decreases.
Since the proportionality is to square of distance, hence change or increase in distance is squared and that many times intensity of electric field decreases. So relation between them is inverse proportionality.
