Rohan walks $4\sqrt{2}$ km towards the north-east, then turns and walks 4 km due south. Where is he now with respect to his starting point?

Explanation

1. 01

   Walking $4\sqrt{2}$ km exactly north-east moves 4 km east and 4 km north, since $\sqrt{4^2 + 4^2} = 4\sqrt{2}$.

2. 02

   4 km south cancels the 4 km north.

3. 03

   He is 4 km east of the start.