A space probe is launched from Earth headed for deep space. At a distance of 10,000 miles from Earth's center, the gravitational force on it is 600 lb. What is the size of the force when it is at each of the following distances from Earth's center?

The size of the mutual gravitational forces between the space probe

and the Earth, at any distance from Earth's center, is ...

(600 lb) x (10,000 mi / distance from Earth's center in miles) ².

= 60,000,000,000 / (distance from Earth's center, in miles) ² pounds.