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Topic Coding-Decoding
Asked 2 times across 2 UPSC exams over 5 years (2021–2026), peaking in 2021.
Key insights
- Most tested in CISF — 1 of 2 PYQs
- Most asked in 2021
- Recurs across 2 years (2021–2026)
How it travelled across exams
First appearance in each exam — the same idea, reframed.
CISF 2021 → ESE 2026
How the concept evolved
Rising — more than half its appearances (2 of 2) are since 2016.
Sample questions
You've seen the pattern — here are a few of the actual PYQs.
ESE2026
The following question is based on the alphabet series : ABCDEFGHIJKLMNOPQRSTUVWXYZ If every alternate letter starting from B of the alphabet is written in small letters, rest all are written in capital letters, how will the month of 'September' be written ?
- A SEpteMbeR
- B SEptEMbEr
- C SEptembER
- D sePTemBeR
Answer key not yet available (pending official release)
Logical Reasoning & DI › Verbal Reasoning
CISF2021
In a certain code language, CAR is written as ECT, DOG is written as FQI and SUN is written as UWP. What is the code word for BET ?
- A DHU
- B EGV
- C CFU
- D DGV ✓
✓ Correct answer: (D)
Logical Reasoning & DI › Verbal Reasoning
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