Question

How far is the center of mass of the Earth-Moon system from the center of the Earth? The Earth's mass is 5.97×1024 kg, the Moon's mass is 7.4×1022 kg, and the distance between their centers is 3.8×108 m.

Answer 1

M is the mass of the Earth, m is the mass of the Moon. r is =3.8•10^8 m
M•x =m• (r-x).
x =m•r/(M+m).

Answer 2

3.76 x 10^8

Answer 3

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