A man travels 12 km towards the West, then 3 km towards the South and then 8 km towards the East. How far is he from the starting point?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → 5 km
Keep a running total of the distance east (or west) and north (or south) of the start; when both are left over, the straight distance is the hypotenuse of a right triangle.
12 km West: 12 km west of the start
3 km South: 12 km west, 3 km south
8 km East: \(12-8=4\) km west, 3 km south
Distance \(=\sqrt{4^{2}+3^{2}}=\sqrt{16+9}=\sqrt{25}=5\) km
He is 5 km from the starting point.
