UKMT Pink Kangaroo, 2017

Algebra Difficulty 1.0 Junior Find the answer United Kingdom

In the number pyramid shown each number is the sum of the two numbers immediately below. What number should appear in the left-hand cell of the bottom row?

(A) $15$ (B) $16$ (C) $17$ (D) $18$ (E) $19$

Figure for this problem

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