In a code, each letter is replaced by its "mirror" letter — A with Z, B with Y, counting equally…
In a code, each letter is replaced by its "mirror" letter — A with Z, B with Y, counting equally from both ends. Coding "B", Manav thinks this is the same "shift 2 forward" rule, so B becomes D. His sister says this is a completely different rule. Who is right?
Who do you think is right? Pick one.
The answer: His sister is right, B becomes Y
Why
Manav is reaching for the shift rule from a different puzzle, since both rules involve swapping one letter for another using the alphabet — but the mechanism here is not a shift at all, it is a mirror. In a mirror-letter code, a letter's position from the START of the alphabet is matched to the same position from the END: A (1st from the start) pairs with Z (1st from the end), B (2nd from the start) pairs with Y (2nd from the end), and so on — the two positions always add up to 27 (letter position + its mirror position = 27, since there are 26 letters). B is the 2nd letter, so its mirror is the 2nd-from-last letter: counting back from Z (26th), 2nd from the end is Y (25th). Test it: A (1st) mirrors to Z (26th): 1+26=27 ✓; B (2nd) mirrors to Y (25th): 2+25=27 ✓ — the pattern holds. His sister is right: B becomes Y under a mirror code — shifting forward by a fixed number and mirroring from both ends are two different rules, even though both just swap letters.
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