Answer:
Please note that the ration between the gravitation force 435 and the mass 44.5
The mass of the Moon is M / 81.3.
The radius of the Moon is R × 0.27.
The gravitational force on the moon would be
G(M/81.3)m/(R×0.27)² = 0.17×GMm/R²
The gravitational force on the moon is smaller by the factor of about 0.17.