How did Newton guess the Inverse Square rule obeyed by the gravitation

1.	How did Newton guess the Inverse Square rule obeyed by the gravitational force
Answer» According to the inverse-square law of gravitaion, the force of gravitation on a planet should decrease as the square of the distance of the planet from the sun.Newton further showed that the gravitational force is proportional to the product of the masses of the two objects.Thus, Newton formulated the universal law of gravitation.\xa0

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