Question

two celestial body are separated by some distance if the mass of any one of the point like bodies is doubled while the mass of other is halved than how far should they be taken so that the gravitational force between them becomes one fourth

Answer 1

Hope u understand the calculations yourself

Answer 2

Since mass of one body is halved and second is doubled, there will be no effect on gravitational force.
Therefore, to reduce gravitational force to quarter, you should Double the distance between them.
By formula it can be expressed as follows.