A10 kilogram of mass iron on earth exerts a downward force of 98 newtons. on the moon this same 10 kilograms of iron i weighed and found to exert a downward force of 16.3 newtons, how is this possible

Well, the Earth and the moon have different gravity; a law force which defines the attraction an object. So this 10kg mass iron would take longer to fall, as the gravity for earth is 9.8 newton.
to find the force:
multiply the mass with the force
10x9.8 = 98
The gravitation force on moon is 1.63
10x1.63=16.3
this is possible due to the different levels of the grvitaion force on moon and earth. We conclude that the attraction of this object is stronger on earth than on the moon.

Divide 108.2 x 10^6 into 1.5 x 10 and the result will be in au (astronomical units)