A taxi goes 20 km towards the East, then 30 km towards the South and then 4 km towards the West. What is the shortest distance between the taxi and its starting point?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 34 km
Keep a running total of the distance east (or west) and north (or south) of the start; when both are left over, the shortest distance is the hypotenuse of a right triangle.
20 km East: 20 km east of the start
30 km South: 20 km east, 30 km south
4 km West: \(20-4=16\) km east, 30 km south
Shortest distance \(=\sqrt{16^{2}+30^{2}}=\sqrt{256+900}=\sqrt{1156}=34\) km
The shortest distance is 34 km.
