My question is based on the weight and mass of object on equator and poles of earth .

the radius of earth at poles is : 6353 km

and at equator it is: 6384

 

due to this lowered radius the acceleration due to gravity will increase near poles and thus the same object would weigh more.

g = GM/R²

the rest of the question is self explainatory.

 

However i would like to add that there is one more very major reason for a weight change which we have not considered.

It is due to the earths rotation.

The earth's rotation causes a centripetal force which decreases the weight of objects on earth near the equator.