Afreena walks 8 km towards the East and then walks 13 km back along the same line. She then turns left and walks 4 km, turns left again and walks 5 km, and finally turns left once more and walks 3 km. How far is she from her starting point?

Difficulty: Medium

Correct Answer: 1 km

Explanation:


Introduction:
This direction–sense question describes Afreena walking forwards, then backtracking past her starting point, and then making a series of left turns. We must compute her final straight-line distance from the starting point. By treating the path as a sequence of movements on a coordinate plane and carefully tracking each turn, we can determine the final displacement and hence the distance.


Given Data / Assumptions:
• Afreena walks 8 km towards the East.• Then she walks 13 km back along the same line (towards the West).• She then turns left and walks 4 km.• Then turns left again and walks 5 km.• Finally, she turns left once more and walks 3 km.• We assume she always turns relative to the direction in which she is currently walking.


Concept / Approach:
We model Afreena's movements using coordinates: East as positive x, West as negative x, North as positive y and South as negative y. Each segment changes her position and, when a turn occurs, also changes her facing direction. By updating coordinates step by step, we can find where she ends up relative to the origin representing her starting point and compute the straight-line distance between these two points.


Step-by-Step Solution:
Step 1: Place the starting point at (0, 0) and let Afreena face East initially. Walking 8 km East takes her to (8, 0).Step 2: She then walks 13 km back along the same line, which means towards the West. From x = 8, moving 13 km West gives x = 8 − 13 = −5. Her position is now (−5, 0) and she is facing West.Step 3: From facing West, a left turn points South. Walking 4 km South takes her to (−5, −4).Step 4: From facing South, another left turn makes her face East. Walking 5 km East from (−5, −4) moves her to (0, −4).Step 5: From facing East, a further left turn makes her face North. Walking 3 km North from (0, −4) moves her to (0, −1).Step 6: Her final position is (0, −1), while her starting point is (0, 0).Step 7: The distance between (0, 0) and (0, −1) is simply 1 km, since the x-coordinate is unchanged and the y-coordinate differs by 1.


Verification / Alternative check:
Summarising the net movements: along the East–West axis she has 8 km East and 13 km West, giving a net 5 km West followed by 5 km East, which cancel to 0. So she ends with no net East–West displacement. Along the North–South axis she has 4 km South and 3 km North, giving a net 1 km South. Thus, she is 1 km to the South of her starting point, confirming the distance of 1 km.


Why Other Options Are Wrong:
Distances like 2 km, 3 km, 5 km or 6 km would require a greater imbalance in the final coordinates, which is not supported by the step-by-step calculation. Those values might arise if you forget one of the turns or mis-handle the backtracking of 13 km. Only 1 km is consistent with both the coordinate approach and the net displacement summary.


Common Pitfalls:
It is easy to forget that walking 13 km back from a position 8 km East of the start will carry Afreena 5 km to the West of the starting point. Some learners also misinterpret left turns when facing West or South. Drawing the path roughly to scale can help make it clear that the final point lies almost but not exactly above the origin, at a distance of 1 km.


Final Answer:
Afreena is finally 1 km away from her starting point.

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