What is the equation to find the Moon Weights of the unknown masses?

Answer 1

The Moon's surface gravity is about 1/6 that of Earth's. So for a given mass, it's weight on the Moon would be its Earth weight/6.

Why is the Moon's gravity 1/6 that of Earth? Gravity is proportional to an object's mass divided by the square of it's radius: M/R^2. The mass of the moon is 1/81 the mass of the Earth, and its size is about 1/3.6 the size of the Earth. Do the math: (1/81) / (1/3.6)^2 = 1/6.

Answer 2

Divide their earthly weight by 6.