What Coding-Decoding Questions Test
- Letter-shifting codes (+n, −n, reversal)
- Substitution codes from example sentences
- Number and symbol coding
- Conditional/mixed coding with multiple rules
Question bank coverage by sub-pattern
How Coding-Decoding Appears in RRB Group D
Coding-Decoding is part of the General Intelligence & Reasoning section (30% of the RRB Group D syllabus).
Coding-Decoding Solved Examples for RRB Group D
12 exam-pattern coding-decoding questions from the practice bank, each with a full solution.
If 'water is life' is coded as 'ram sita geeta', 'life is beautiful' is coded as 'sita maya reeta', and 'water beautiful earth' is coded as 'ram maya heera', then how is 'earth' coded?
- A.ram
- B.maya
- C.heeraCorrect
- D.sita
Solution
water is life = ram sita geeta; life is beautiful = sita maya reeta; water beautiful earth = ram maya heera. From the first and second sentences, 'life is' is 'sita'. Then 'water = ram' and 'beautiful = maya'. Therefore, 'earth' must be 'heera'.
In a certain code, 'SIMPLE' is written as 'TJNQMF'. How is 'TRULY' written in that code?
- A.USVMZCorrect
- B.VQVMZ
- C.USVZM
- D.VSUMZ
Solution
Each letter is shifted by +1 position. S -> T, I -> J, M -> N, P -> Q, L -> M, E -> F. Similarly, T -> U, R -> S, U -> V, L -> M, Y -> Z. Therefore, TRULY is coded as USVMZ.
In a certain code, 'PENCIL' is written as '$@=©*!', and 'PAPER' is written as '$?$=©'. How is 'CLIP' written in that code?
- A.©*!$
- B.©*=$
- C.*!=$Correct
- D.*=$©
Solution
P is coded as $, E as @, N as =, C as ©, I as *, and L as !. Thus, C is coded as ©, L as !, I as *, and P as $. Therefore, CLIP is coded as *!=$
In a coded language, 'SUMMER' is written as 'RUNNDQ' following a pattern of subtracting the floor number value from 27 (A=1, B=2,..., Z=26), then what is the code for 'WINTER'?
- A.VJMFDQ
- B.VHMFDQCorrect
- C.VHMFAQ
- D.VHMCDQ
Solution
Subtracting each letter's position from 27: W(23) -> 4 (D), I(9) -> 18 (R), N(14) -> 13 (M), T(20) -> 7 (G), E(5) -> 22 (V), R(18) -> 9 (I). Therefore, 'WINTER' becomes 'VHMFDQ'.
If A = 1, B = 2, C = 3... Z = 26, then what is the value of the word 'CAT'?
- A.24Correct
- B.6
- C.60
- D.30
Solution
A = 1, C = 3, T = 20. Therefore, CAT = C + A + T = 3 + 1 + 20 = 24.
If A=2, M=26, Z=52, then BET = ?
- A.54Correct
- B.44
- C.64
- D.72
Solution
A=2, B=4, C=6, D=8, E=10, F=12, G=14, H=16, I=18, J=20, K=22, L=24, M=26, N=28, O=30, P=32, Q=34, R=36, S=38, T=40, U=42, V=44, W=46, X=48, Y=50, Z=52. BET = 4+10+40 = 54
If A=2, B=4, C=6, ..., Z=52, then what is the value of 'BAT'?
- A.22
- B.46Correct
- C.44
- D.45
Solution
A=2, B=4, T=40. BAT = 4 + 2 + 40 = 46
If 'DELHI' is coded as 'EFMIJ', then how will 'BOMBAY' be coded as?
- A.CPNCBZCorrect
- B.CPNCAZ
- C.CPNCBX
- D.CPOCBZ
Solution
Each letter is shifted by +1 position. D -> E, E -> F, L -> M, H -> I, I -> J. Similarly, B -> C, O -> P, M -> N, B -> C, A -> B, Y -> Z. Therefore, BOMBAY is coded as CPNCBZ.
In a certain code, if JUNGLE is written as KVOHMF, how is DESERT written?
- A.EFTFSUCorrect
- B.EGTFSU
- C.EFTGSU
- D.EFTHSU
Solution
JUNGLE -> KVOHMF: J+1=K, U+1=V, N+1=O, G+1=H, L+1=M, E+1=F. Each letter +1. DESERT: D+1=E, E+1=F, S+1=T, E+1=F, R+1=S, T+1=U = EFTFSU.
If in a certain code, 'LUCKY' is coded as 'MVDLZ', then how will 'CHARM' be coded in that language?
- A.DIBSNCorrect
- B.DIBSO
- C.DSBIN
- D.DISBN
Solution
Each letter is shifted by +1 position. L -> M, U -> V, C -> D, K -> L, Y -> Z. Similarly, C -> D, H -> I, A -> B, R -> S, M -> N. Therefore, CHARM is coded as DIBSN.
In a certain code, if 'HOUSE' is written as 'GVPTI' following a floor-based pattern where each letter is shifted based on its floor number (H is on the 8th floor, O on the 15th, etc.), what will be the code for 'BOARD'?
- A.CPBSE
- B.CNBQECorrect
- C.CPCAE
- D.CNCSE
Solution
The coding pattern shifts each letter by +1, +1, +1, +1, +1, respectively. B(+1) -> C, O(+1) -> N, A(+1) -> B, R(+1) -> Q, D(+1) -> E. Thus, 'BOARD' becomes 'CNBQE'.
If E=5, RED=27, then DANCE=?
- A.32
- B.34
- C.29Correct
- D.31
Solution
E=5, RED = 18+5+4 = 27. DANCE = 4+1+14+3+5 = 27. However, the options are incorrect. DANCE = 4+1+14+3+5 = 27. The correct answer is 27. The options should be updated.
Coding-Decoding — Frequently Asked Questions
What is the first thing to check in a coding question?
Compare letter positions of the word and its code. A constant gap means a shift code; a variable but symmetric gap usually means reversal; no positional relation means substitution — then match letters across the given examples.
How are sentence-coding questions solved quickly?
Find a word that repeats across two coded sentences — its code is the token both code-sentences share. Eliminate word by word instead of decoding everything.
How many Coding-Decoding practice questions does Parikshala have for RRB Group D?
53 exam-pattern Coding-Decoding questions for RRB Group D Reasoning, each with a step-by-step solution. Practice is free — no sign-up needed to start.