Algebra II
posted by MJ .
The weight of a body varies inversely as the square of its distance from the center of the earth. If the radius of the earth is 4000 mi, how much would a 200 lb man weigh 1000 mi above the surface of the earth?

w = k(1/d^2)
when d = 4000 , w = 200
200 = k(1/16000000)
k = 200(16000000)
when d = 5000
w = 200(16000000)/5000^2 = 128