Problems from Simplification in expressions with factorials

Development:

$${\displaystyle \frac{8!\cdot 3!}{9!\cdot 4!}}={\displaystyle \frac{\cancel{8!}\cdot \cancel{3!}}{9\cdot \cancel{8!}\cdot 4\cdot \cancel{3!}}}={\displaystyle \frac{1}{9\cdot 4}}={\displaystyle \frac{1}{36}}$$

Solution:

${\displaystyle \frac{1}{36}}$

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