Maths Olympiad Prep

Library / /161 of 413

, 1999

Algebra Difficulty 1.0 Junior Find the answer Canada

The expression n!n! means the product of the positive integers from 11 to nn. For example, 5!=1×2×3×4×55! = 1 \times 2 \times 3 \times 4 \times 5. The value of 6!4!6! - 4! is

(A) 22 (B) 1818 (C) 3030 (D) 716716 (E) 696696

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