I have done most of the work on the problem written below, but the more I look at it, the more I am not sure whether I should leave the pounds as they are instead of converting them to kilograms. If I leave it as 200 lbs, are the number plug-ins going to be wrong? I am using the formula g = 6.67x10^-11 x 6 x 10^24 / (2 x 6.40 x 10^3)^2 = 2.44 m/s^2 then W=mg which I have calculated at 20 x 2.44 = 48.8 N A building is 6400 km high. On the bottom floor a person weighs 200 pounds when stepping on a spring scale. How much would the person weigh on the same scale if she were standing on the top floor? I know that 6400 km is also the radius of the earth so that the top floor is 2R from the earth's center. thanks!