Question

A man goes 3km north and then 4km west find how far away is he from his initial position

Answer 1

Since the earth is spherical you will get different answers depending on where you start. Generally the answer for the most part will be approximately 5 km. As one get close to or on a pole you get more interesting answers. Near the North pole a person can walk not toward the for 3 km and East half way around the earth in 4 km, making the starting point a little over 5.54 km away. At the other end starting on the South pole, you can walk north 3 km then East is a circle around the pole, so no matter how far you walk the distance would be 3 km.