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UKMT Intermediate Mathematical Challenge, 2024

Number theory Difficulty 2.0 Junior Find the answer United Kingdom

Factorial $n$ , written $n!$ , is defined by: $n! = 1 \times 2 \times 3 \times \cdots \times n$ . What is the remainder when $1! + 2! + 3! + 4! + 5! + 6! + 7! + 8! + 9! + 10!$ is divided by 5?

(A) $0$ (B) $1$ (C) $2$ (D) $3$ (E) $4$

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