Explanation:
To solve this problem, we need to determine the route that will bring person X back to the starting point based on his initial movements.
1. Understanding the initial movements:
Let’s assume person X starts at the point $(0, 0)$ on a grid.
First movement: 3 km north. This moves X from $(0, 0)$ to $(0, 3)$.
Second movement: 3 km west. This moves X from $(0, 3)$ to $(-3, 3)$.
Third movement:ย 4 km south. This moves X from $(-3, 3)$ to $(-3, -1)$.
At this point, X is at $(-3, -1)$.
2. Calculating the distance to return to the starting point $(0, 0)$:
To return to $(0, 0)$ from $(-3, -1)$, X needs to:
– Move 3 km east to change the x-coordinate from $-3$ to $0$.
– Move 1 km north to change the y-coordinate from $-1$ to $0$.
3. Determining the correct route from the options:
We need to find the route from the options that involves moving 3 km east and 1 km north to return to the starting point.
Option (a): 3 km east, then 2 km south.
Moving 3 km east would bring X to $(0, -1)$, and moving 2 km south would bring X to $(0, -3)$.
This does not return X to $(0, 0)$.
Option (b): 3 km east, then 1 km north.
Moving 3 km east would bring X to $(0, -1)$, and moving 1 km north would bring X to $(0, 0)$.
This returns X to $(0, 0)$.
Option (c): 1 km north, then 2 km west.
Moving 1 km north would bring X to $(-3, 0)$, and moving 2 km west would bring X to $(-5, 0)$.
This does not return X to $(0, 0)$.
Option (d): 3 km south, then 1 km north.
Moving 3 km south would bring X to $(-3, -4)$, and moving 1 km north would bring X to $(-3, -3)$.
This does not return X to $(0, 0)$.
4. Conclusion:
The correct route that will bring person X back to the starting point is option (b): 3 km east, then 1 km north.
The correct answer is (b) 3 km east, then 1 km north.