Ira walks 40 m towards the North from a well. She turns left and walks 9 m, and then turns left again and walks 80 m. What is the shortest distance between Ira and the well now?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 41 m
A left turn moves the facing direction one step anticlockwise (North → West → South). Keep a running total of the distance from the well; then use Pythagoras.
Facing North, 40 m: 40 m north of the well
Turns left, now facing West, 9 m: 40 m north, 9 m west
Turns left, now facing South, 80 m: \(80-40=40\) m south, 9 m west
Shortest distance \(=\sqrt{9^{2}+40^{2}}=\sqrt{81+1600}=\sqrt{1681}=41\) m
The shortest distance is 41 m.
