You weigh slightly less at the equator than at the geographic North or South pole. This is because of the Earth's rotation. At the equator, some of the force of gravity contributes to the centripetal force required to make you move in a circle around the Earth's axis, so your apparent weight decreases. If the radius of the Earth is RE = 6378 km, then what is the ratio of your weight at the equator versus at the pole, We/Wp