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UKMT Junior Mathematical Challenge, 2022

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

In the number pyramid shown, each cell above the bottom row contains the sum of the numbers in the two cells immediately below it. The sum of the numbers in the bottom row is 17. What is the central number of the bottom row?

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

Figure for this problem

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