Radha moves towards South-East a distance of 7 km, then she moves towards West and travels a distance of 14 km. From here she moves towards North-West a distance of 7 km and finally she moves a distance of 4 km towards east. How far is she now from the starting point?

Break diagonal movements into North-South and East-West components: SE 7 km gives 7/√2 km South and 7/√2 km East (approximately 4.95 km each). NW 7 km gives 7/√2 km North and 7/√2 km West. The SE and NW movements cancel each other's diagonal components. West 14 km minus East 4 km leaves 10 km West from origin. Final position is 10 km away.