I'm not really good at geometry, and I was discussing with a friend about GPS. Let's for fun say that they are geostationary (we ignore the poles), then how many sattelites do we need to cover the entire earth, such that at any given point on earth at least 3 satelites are visible.
If we use this info then how is it possible to calculate how many satelites are needed, and how far apart they should be? My guess would be to divide the 360 degress with the 75 degress that each satelite can cover, and then multiply by 3.
360/(75)*3 = 14.4 ~ 15 satelites
Is that statement true?