The gravitational force F between two bodies of masses M and m kept at a distance d from each other is

F = \(G \times \frac{m \times M}{d^2}\)

The force between two bodies is inversely proportional to the square of the distance between them. That is,

F ∝ \(\frac{1}{d^2}\)

Therefore, if we double the distance between two bodies, the gravitational force becomes one-fourth and if we halve the distance between two bodies, then the gravitational force becomes four times.