When the distance between the centres of the two bodies is doubled, the magnitude of the gravitational force, in terms of F, will now be …

Question

The magnitude of the gravitational force exerted by one body on another body is F. When the distance between the centres of the two bodies is doubled, the magnitude of the gravitational force, in terms of F, will now be …

Answer 1

$F= \dfrac{G \times M_1 \times M_2}{R^2}$

if R is doubled

$F=\dfrac{G M1M2}{4R^2}$

Force = 1/4 the original

Answer 2

...the inverse square law implies that the force will be "1/4" of the original F units. (If the distance is increased by a factor of 2, then distance squared will increase by a factor of 4.)