Directions — RRB NTPC Reasoning
This topic carries roughly 6% of General Intelligence & Reasoning's 30 questions. Every direction problem reduces to plotting coordinates: track your (x, y) position and current facing direction after each move, then compute the straight-line distance and direction from the starting point.
1. What RRB NTPC actually asks
Expect direct movement-tracing problems (walk N, turn, walk again — find final distance/direction from start), and shadow-based direction problems (using the sun's position at a given time of day to determine facing direction).
2. The coordinate method
Treat North as +y, South as −y, East as +x, West as −x. Track your position as a running (x, y) coordinate, updating it after every stated move. At the end, the straight-line distance from the origin is found using the Pythagorean theorem on the net x and y displacement, and the direction is read from the sign and relative size of the net x and y values.
3. Left and right turns
A right turn rotates your facing direction clockwise: North→East→South→West→North. A left turn rotates counter-clockwise: North→West→South→East→North. Track your current facing direction explicitly after every turn — don't try to infer it after the fact.
4. Shadow-direction rule
At sunrise, the sun is in the East, so shadows fall toward the West. At sunset, the sun is in the West, so shadows fall toward the East. A person's shadow is always cast on the side opposite the sun.
Once you know which direction the shadow falls, and where the shadow falls relative to the person (left, right, in front, behind), you can determine which direction the person is facing using the same left/right rotation logic as turns.
Worked examples
Q1. A man walks 5 km north, then 3 km east, then 5 km south. How far is he from his starting point, and in which direction?
Pick an option to check your answer.
Show explanation
Solution. Plot the moves: start (0,0). North 5 km → (0,5). East 3 km → (3,5). South 5 km → (3,0).
The final position is (3,0) — the north and south movements cancel exactly (5 km each), leaving only the 3 km eastward displacement. He is 3 km from the start, in the East direction. Answer: (a).
Q2. One morning, Suresh was walking such that his shadow fell exactly to his left. Which direction was he facing?
Pick an option to check your answer.
Show explanation
Solution. In the morning, the sun is in the East, so shadows fall toward the West. Suresh's shadow is to his West, and it falls to his LEFT.
Using the rotation rule: when facing North, your left side points West — this is the only facing direction where "left" corresponds to "West." Answer: (a).
6. Common traps
- Adding up all distances walked as if that were the answer, rather than computing the net straight-line distance from start to finish. Movements in opposite directions (like 5 km north then 5 km south) can cancel out partially or fully.
- Confusing left and right turn rotation direction. Right turns go clockwise (N→E→S→W); left turns go counter-clockwise (N→W→S→E) — easy to reverse under time pressure.
- Forgetting that shadows fall OPPOSITE the sun, not toward it. At sunrise (sun in the East), shadows point West, not East.
- Applying the coordinate method without tracking facing direction separately from position — turns change facing direction, but only actual "walk" instructions change position.
7. Guessing strategy
If a question asks only for direction (not exact distance), the net x and y sign alone (positive/negative) is enough to determine the direction without computing the exact distance — this saves calculation time when the exact distance isn't needed.
Summary
- Directions is roughly 6% of General Intelligence & Reasoning's 30 CBT 1 questions.
- Track position as a running (x, y) coordinate: North=+y, South=−y, East=+x, West=−x.
- Right turns rotate clockwise (N→E→S→W); left turns rotate counter-clockwise (N→W→S→E).
- Shadows fall opposite the sun: West at sunrise, East at sunset.
- The final answer is the net straight-line distance and direction from start, not the total distance walked.
- Track facing direction separately from position — only "walk" moves change position, only "turn" instructions change facing.
