Question 1

In a certain coding system, each letter is replaced by the letter that comes 3 positions after it in the English alphabet. For example, A is coded as D, B is coded as E, and so on. If a letter reaches beyond Z, it wraps around to the beginning (so X→A, Y→B, Z→C). Using this rule, how would the word 'PLAY' be coded?

Accepted Answer

This is a letter-shift coding question where each letter shifts forward by 3 positions in the alphabet with wraparound. P→S, L→O, A→D, Y→B, giving SODB.

Question 2

In a code language, consonants are replaced by the next consonant (B→C, C→D, D→F, F→G, etc., skipping vowels), and vowels remain unchanged. What is the code for 'FRIEND'?

Accepted Answer

F→G, R→S, I remains I, E remains E, N→P, D→F. The code is GSIEPF.

Question 3

In a code, each letter is replaced by the letter 2 positions before it in the alphabet (B→Z, C→A, D→B, and so on, wrapping around). What is the code for 'DOG'?

Accepted Answer

D→B (2 before D), O→M (2 before O), G→E (2 before G). The code is BME.

Question 4

In a certain code, each letter is replaced by a number: A=1, B=2, C=3, ..., Z=26. What is the numeric code for the word 'CAT'?

Accepted Answer

C=3, A=1, T=20. The numeric code is 3-1-20 or 3120.

Question 5

In a certain code, each letter is replaced by the letter that comes 3 positions after it in the English alphabet. For example, A is coded as D, B is coded as E, and so on. What is the code for the word 'HELLO'?

Accepted Answer

Apply the +3 letter shift rule to each letter: H→K, E→H, L→O, L→O, O→R. The code is KHOOR.

Question 6

In a certain coding system, each letter is replaced by the letter that comes 3 positions after it in the English alphabet, and the positions wrap around (Z wraps to C). Additionally, vowels are replaced by the number corresponding to their position in the vowel sequence (A=1, E=2, I=3, O=4, U=5). Using this rule, what is the code for the word 'PHONE'?

Accepted Answer

The word PHONE is encoded by applying two rules: consonants shift 3 positions forward (with wraparound), and vowels are replaced by their position number in the vowel sequence (A=1, E=2, I=3, O=4, U=5). P→S, H→K, O→4, N→Q, E→2. Therefore, PHONE = SK4Q2.

Question 7

In a certain code, each letter is replaced by the letter that comes 3 positions after it in the English alphabet. For example, A→D, B→E, etc. If a letter goes beyond Z, it wraps around (X→A, Y→B, Z→C). What is the code for the word 'LOGIC'?

Accepted Answer

Apply the +3 letter shift rule consistently to each letter: L→O, O→R, G→J, I→L, C→F. The coded word is ORJLF.

Question 8

In a code, each letter is replaced by the letter that is 5 positions after it, except for vowels which are replaced by the vowel 2 positions after them in the vowel sequence (A→I, E→O, I→U, O→A, U→E). What is the code for 'BELIEVE'?

Accepted Answer

B(consonant)→G, E(vowel)→O, L(consonant)→Q, I(vowel)→U, E(vowel)→O, V(consonant)→A, E(vowel)→O. The coded word is GOQUOAO.

Question 9

In a code language, the position of each letter in a word is reversed, and then each letter is replaced by the letter 2 positions before it in the alphabet (with wraparound: A→Y, B→Z). What is the code for 'SMART'?

Accepted Answer

Step 1 - Reverse SMART: TRMAS. Step 2 - Apply -2 shift: T→R, R→P, M→K, A→Y, S→Q. The coded word is RPKYQ.

Question 10

In a certain code, consonants are assigned numbers based on their position in the alphabet (B=2, C=3, D=4, etc.), and vowels are assigned as A=1, E=5, I=9, O=15, U=21. What is the numerical code for 'TRAIN'?

Accepted Answer

T(20)→20, R(18)→18, A(1)→1, I(9)→9, N(14)→14. The numerical code is 20-18-1-9-14.

Question 11

In a code language, vowels are replaced by the next vowel in sequence (A→E, E→I, I→O, O→U, U→A), and consonants remain unchanged. What is the code for 'PROBLEM'?

Accepted Answer

Apply the vowel-shift rule: P(consonant)→P, R(consonant)→R, O(vowel)→U, B(consonant)→B, L(consonant)→L, E(vowel)→I, M(consonant)→M. The coded word is PRUBLIM.

SSC CPO Coding Decoding

SSC CPO Coding Decoding — Past Exam Questions

Coding Decoding— Rules & Concept

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60-Second Revision — Coding Decoding