RRB Group D Reasoning Questions: The Short Answer
In the RRB Group D Computer Based Test, General Intelligence and Reasoning has 30 of the 100 questions, the largest single section (the full paper is 90 minutes; source: CEN 09/2025, as summarised in our RRB Group D eligibility note). Most of these questions come from a small set of topics: analogy, series, coding-decoding, blood relation, directions and missing numbers. Each topic has one or two rules that solve most questions; learn the rule, then practise until you can apply it in under 30 seconds.
Key takeaway: Write the alphabet positions (A = 1 ... Z = 26) and their opposites (A↔Z, sum 27) once at the start of the exam. Most coding, letter-series and letter-analogy questions are solved from that line. Every answer below was computed in Python.
Topic-wise Rules (Quick Table)
| Topic | What to check first |
|---|---|
| Number analogy | n × (n + 1), n² ± k, n³ ± k |
| Letter analogy | Move of each letter (+1, +2, ... ); wrap after Z |
| Number series | Differences; then differences of differences; then × n + n |
| Letter-cluster series | Move inside the cluster and move of the first letter |
| Coding-decoding | Shift, reverse + shift, opposite letters, sum of positions |
| Blood relation | Draw the tree: generation levels and gender |
| Direction turns | Add the turns (clockwise +, anticlockwise −), then count 45° steps |
| Missing number in sets | (a + b) × k, a² + b², a × b − a |
RRB Group D Reasoning Questions with Solutions
Number analogy
Q1. 9 : 90 :: 12 : ?
9 × 10 = 90, so 12 × 13 = 156.
Letter-cluster analogy
Q2. DGK : EJP :: PRY : ?
The letters move +1, +3, +5 (after Z comes A again). PRY → QUD.
Number series
Q3. 5, 6, 10, 19, ?, 60
The differences are 1², 2², 3², 4², 5² = 1, 4, 9, 16, 25. So ? = 19 + 16 = 35.
Q4. 3, 4, 10, 33, ?, 685
Each term = previous × n + n for n = 1, 2, 3, ...: 3×1+1 = 4, 4×2+2 = 10, 10×3+3 = 33, so ? = 33×4+4 = 136.
Letter-cluster series
Q5. BEH, GJM, LOR, ?, VYB
Inside each cluster the letters move +3; the first letters move +5 (B, G, L, Q, V). So ? = QTW.
Coding-decoding (reverse and shift)
Q6. In a certain code, TRAIN is written as PKCTV. How is PLANE written in that code?
Reverse the word and move each letter 2 places forward: TRAIN → NIART → PKCTV. So PLANE → ENALP → GPCNR.
Coding-decoding (opposite letters)
Q7. In a certain code, WATER is written as DZGVI. How is FIELD written?
Each letter is replaced by its opposite (A↔Z, B↔Y, ... ; positions add up to 27). So FIELD → URVOW.
Coding-decoding (number code)
Q8. If MANGO is coded as 50, how is GRAPES coded?
Code = sum of the alphabet positions: M13 + A1 + N14 + G7 + O15 = 50. GRAPES: G7 + R18 + A1 + P16 + E5 + S19 = 66.
Blood relation
Q9. Ritu is the daughter of Sunil. Sunil is the brother of Kamla. Kamla is the mother of Arjun. How is Ritu related to Arjun?
Ritu's father Sunil and Arjun's mother Kamla are brother and sister, so Ritu and Arjun are cousins: Ritu is Arjun's cousin.
Coded blood relation
Q10. 'P + Q' means P is the father of Q; 'P × Q' means P is the sister of Q; 'P − Q' means P is the wife of Q. If A × B + C, how is A related to C?
A is the sister of B, and B is the father of C. So A is the father's sister of C: aunt.
Direction sense (turns)
Q11. A man faces North. He turns 90° clockwise, then 135° anticlockwise, then 180° clockwise. Which direction is he facing now?
Take clockwise as + : net turn = 90 − 135 + 180 = 135° clockwise. From North, 135° clockwise is South-East.
Missing number in sets
Q12. (5, 4, 18); (7, 3, 20); (6, 9, ?)
Third = (first + second) × 2: (5 + 4) × 2 = 18, (7 + 3) × 2 = 20. So ? = (6 + 9) × 2 = 30.
Tips for RRB Group D Reasoning
- Attempt reasoning first or second. It has the most questions and the answers can be checked quickly.
- Check every option against the rule. In number analogy, test the rule on the given pair before applying it.
- For blood relations, mark gender. "Brother", "son" and "husband" tell you the person is male; use that when a question asks for an exact relation.
- For direction turns, add degrees. It is faster and safer than turning step by step.
RRB Group D Reasoning FAQs
How many reasoning questions come in RRB Group D?
30 questions out of 100 in the Computer Based Test, as per the exam pattern in CEN 09/2025.
Which reasoning topics should I practise first?
Coding-decoding, series (number and letter), analogy, blood relation and direction sense. They are quick to learn and appear in almost every shift.
How should I start preparing Group D reasoning?
Group D recruits for Level 1 posts (Class 10, ITI or NAC qualification). Practise one-rule questions like the ones above until they are fast, then move to mixed full-length tests.
Practice Next
- Tests: RRB Group D Reasoning Mock Test 05, RRB Group D Reasoning Mock Test 07, RRB Group D Direction Sense Test 03, RRB Group D Coding-Decoding Test 03, RRB Group D Reasoning Mini Test 05.
- Related notes: coding-decoding tricks, direction sense questions, blood relation questions, RRB Group D salary 2026. Browse all study notes.