Maths Olympiad Prep

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, 2024

Number theory Difficulty 2.0 Junior Find the answer United Kingdom

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

(A) 00 (B) 11 (C) 22 (D) 33 (E) 44

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