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UKMT Grey Kangaroo, 2025

Number theory Difficulty 2.0 Junior Find the answer United Kingdom

Julia wants to fill in each $\square$ with a different prime number less than 20 so that the value of $X$ is an integer. What is the maximum possible value of $X$ ? $X = \dfrac{\square+\square+\square+\square+\square+\square}{\square}$

(A) $20$ (B) $14$ (C) $10$ (D) $8$ (E) $6$

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