# Are you good at summation

Algebra Level 5

$\large \sum_{n=1}^{25}\frac{1}{n(n+1)(n+2)(n+3)(n+4)(n+5)}$ If $$M$$ denote the value of the summation above, with $$M = \frac a b$$ for coprime positive integers, find $$a+b$$.

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