Number theoryDifficulty 2.0JuniorFind the answerUnited Kingdom
Factorial n, written n!, is defined by: n!=1×2×3×⋯×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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