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UKMT Junior Mathematical Challenge, 2026

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

The numbers $1, 2, 3, 4, 5$ , and $6$ are to be placed in the six circles shown so that: (i) there is one number in each circle, and (ii) the sum of the numbers in each pair of adjacent circles is a prime number. The number $1$ has already been placed. Which number should go in the circle marked $x$ ?

(A) $2$ (B) $3$ (C) $4$ (D) $5$ (E) $6$

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