Two balls, each with a mass of 0.819 kg,

exert a gravitational force of 8.76 × 10^−11 N on each other.
How far apart are the balls? The value
of the universal gravitational constant is
6.673 × 10−11 Nm2/kg2.
Answer in units of m.

1 answer

Try solving the law of gravity equation:

8.76*10^-11 N = G *(0.819 kg)^2/R^2

to get the value of R. With your value of G, you will get R in meters.