F = G mM / r^2, where
F = gravitational force between the earth and the moon,
G = Universal gravitational constant = 6.67 x 10^(-11) Nm^2/(kg)^2,
m = mass of the moon = 7.36 × 10^(22) kg
M = mass of the earth = 5.9742 × 10^(24) and
r = distance between the earth and the moon = 384,402 km
F
= 6.67 x 10^(-11) (7.36 × 10^(22) 5.9742 × 10^(24) / (384,402 )^2
= 1.985 x 10^(26) N