Unit 10 · Coded Language Cipher
Secret Letter Code — Crack the Cipher
Lesson 1 of 3
Cipher questions reward one habit: find the fixed letter shift from the examples, then apply it letter-by-letter to the target word.
Substitution codes appear regularly on Selective TS — often as a mid-paper puzzle when you compare two known words to lock the rule.
The examiner checks whether you can infer a consistent +N (or −N) shift from paired plaintext/ciphertext and apply it without mixing letters.
Two encoded words are given with their originals. You encode or decode a third word using the same shift, watching wrap-around at A–Z.
Best approach: Align letters of one pair and count the shift (e.g. A→D is +3). Apply that shift to every letter of the new word. Verify with the second example before picking an option.
Question
In a secret code, each letter of the alphabet is replaced by another letter using the same rule throughout.
- APPLE is written as DSSOH
- CAKE is written as FDNH
Using the same code, what would MANGO be written as?
Using the same code, what would MANGO be written as?
Select an answer to see the explanation.
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