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UKMT Pink Kangaroo, 2021

Number theory Difficulty 2.0 Junior Find the answer United Kingdom

The numbers from 1 to 6 are to be placed at the intersections of three circles, one number in each of the six squares. The number 6 is already placed. Which number must replace $x$ , so that the sum of the four numbers on each circle is the same?

(A) $1$ (B) $2$ (C) $3$ (D) $4$ (E) $5$

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