Direction, Distance, Order, and Ranking
Key Takeaways
- Direction questions should be drawn on a north-east-south-west grid, with each turn interpreted from the person's current facing direction.
- The exam may ask for final displacement, total distance travelled, direction from start, or shortest distance, and these are different outputs.
- Ranking questions rely on clean formulas: opposite-side position equals total minus known position plus one, and total can equal left plus right minus one.
- Order comparison questions should be converted into a chain before deciding highest, lowest, nearest, farthest, earlier, or later.
Spatial Reasoning With Small Diagrams
Direction and ranking questions reward candidates who convert words into a picture or chain. They are not difficult because the math is advanced; they are difficult because a left turn, right turn, opposite-side rank, or comparison word can be misread. In RRB NTPC, these items are valuable because they can be solved quickly when the setup is clean.
Use rough work early. A tiny compass, a line of positions, or a height chain prevents rereading. The CBT clock punishes memory-heavy solving. If you hold a four-step path in your head and then compare options, one turn may disappear. If you draw the path, the final relation is visible.
Direction Basics
| Facing now | Left turn becomes | Right turn becomes | Opposite becomes |
|---|---|---|---|
| North | West | East | South |
| South | East | West | North |
| East | North | South | West |
| West | South | North | East |
A common mistake is treating right as east and left as west every time. That is true only when the person is facing north. Direction questions usually say the person turns left or right after moving, so the turn depends on the current facing direction.
Distance: Path Length vs Displacement
The total distance travelled is the sum of all movement. The shortest distance from the start is displacement. A person who walks 6 metres north, 8 metres east, and 6 metres south has travelled 20 metres, but ends 8 metres east of the start. If the north-south and east-west parts do not cancel fully, use a right triangle.
For example, if a candidate walks 9 metres north and 12 metres east, the shortest distance from the start is 15 metres by the 9-12-15 triangle. If the question asks how far he walked, the answer is 21 metres. Read the output word carefully: distance walked, distance from start, direction from start, or final facing.
In railway-themed wording, do not let stations and platforms distract you. A station is just a point, a road is just a segment, and a turn is still a turn. Mark the starting point as S, every turn as a corner, and the final point as F.
Order and Ranking Formulas
Ranking questions use positions from left, right, top, bottom, front, back, earlier, later, higher, or lower. If one person's position from one end and the total number are known, the opposite-side position is:
opposite-side position = total - known position + 1
The +1 is important because the person is counted in both directions. Forgetting it creates a common wrong answer. If Ravi is 14th from the left in a row of 50, his position from the right is 50 - 14 + 1 = 37th.
If the same person's rank from both ends is known and the total is not given, use:
total = left rank + right rank - 1
If A is 9th from the front and 18th from the back, there are 9 + 18 - 1 = 26 people. Subtract one because A was counted twice.
Comparison Chains
Order comparison questions say things like A is taller than B, C is shorter than A, D is taller than C but shorter than B. Write symbols immediately. For height, use > for taller. For age, use > for older. For ranking by marks, decide whether greater means better before drawing.
The clean chain may not be complete. If the statements are A > B and C > D, but nothing connects the two pairs, you cannot decide the tallest overall. RRB NTPC distractors often assume a connection that the statements never give. Mark only what must be true.
Practical Rough-Work Rules
- Draw north at the top before starting a direction problem.
- Record final facing separately from final location.
- Circle the endpoint before reading options.
- For ranks, write total, known side, and asked side.
- For comparisons, build a chain and note disconnected groups.
Common Output Words
Train yourself to underline the requested output. How far did he walk asks for total path length. How far is he from the starting point asks for shortest distance or displacement. In which direction is he now asks for final facing, while in which direction is he from the start asks for the line from start to finish. In ranking, between excludes the two named people, but total-row formulas count the person whose rank is given. These wording checks prevent most near-miss answers.
Also mark units. A path in metres, a rank in people, and an order in days cannot be compared casually. If the options mix direction and distance, decide the requested form before doing any arithmetic.
Time Management
Direction and ranking questions should usually be fast. If a direction problem grows into many turns, skip drawing to scale; draw only the sequence and net movement. If a ranking problem includes two people crossing positions or a group inserted between ranks, slow down and label every condition. These are still manageable, but they need exact accounting.
The penalty-aware rule is simple: if your diagram and the wording disagree, do not trust the option that looks closest. Rebuild the diagram from the start. A fresh 20-second redraw is cheaper than losing one-third of a mark on a preventable turn or count error.
A person faces east, turns left and walks 6 m, turns right and walks 8 m, then turns right and walks 6 m. Where is the person from the starting point?