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UKMT Junior Kangaroo, 2026

Combinatorics Difficulty 1.0 Junior Find the answer United Kingdom

The five keys shown fit the five padlocks. The numbers on the keys are coded by letters on the padlocks. Which number is written on the remaining key?

(A) $282$ (B) $284$ (C) $382$ (D) $823$ (E) $824$

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