Question

An object’s weight depends

on its height above the surface of the earth. If a man weighs 190 pounds on the
surface of the earth, then the man's weight in pounds (W) x miles above the
surface is approximated by the formula: 

W = (190

⋅ 4,000^2) / (4,000+x)^2 

For each problem below, approximate the weight
of a 190-pound person at the given height above the surface of the earth. 

Remember, 1 mile = 5,280 feet. 

1. 100 miles 

2. 1,000 miles 

3. 1,056,000 feet 

4. 10,000,000 feet  

Answer 1

so since your equation has x in miles, then change 3 and 4 from feet to miles by dividing them by 5280. then input each of those numbers into your formula.
example: 1. W = (190 * 4000^2)/ (4000 + 100)^2

if you are curious, your equation is derived from this: F(g) = G (m1)(m2)/(r^2)
where m1 and m2 are the two masses (the earth and the person) and r is the distance between, from center to center.