UKMT Pink Kangaroo, 2026

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

What is the value of the expression $(1-2)-(3-4)-(5-6)-\ldots-(2025-2026)$ ?

(A) $-1013$ (B) $-1011$ (C) $1011$ (D) $1013$ (E) $2024$

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