UKMT Pink Kangaroo, 2015

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

The figure shows seven regions enclosed by three circles. We call two regions neighbouring if their boundaries have more than one common point. In each region a number is written. The number in any region is equal to the sum of the numbers of its neighbouring regions. Two of the numbers are shown. What number is written in the central region?

(A) $-6$ (B) $6$ (C) $-3$ (D) $3$ (E) $0$

Figure for this problem

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