If Kiran walked 9 metres towards the north and 12 metres towards the west, how far is she from the point where she began to walk?

Explanation

Walking 9 m north and then 12 m west creates a right-angled triangle. The straight-line distance from the starting point is √(9² + 12²) = √225 = 15 metres. This is the familiar 9–12–15 Pythagorean triple.