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UKMT Senior Mathematical Challenge, 2023

Number theory Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

When completed correctly, the cross number is filled with four three-digit numbers. What digit is $*$ ? Across: 1. A square; 3. A fourth power. Down: 1. Twice a fifth power; 2. A cube.

(A) $0$ (B) $1$ (C) $2$ (D) $4$ (E) $6$

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