try it

what is 30!/27!3!

$\begin{array}{rcll} \dbinom{30}{3} &=& \frac{30}{3} \cdot \frac{29}{2} \cdot \frac{28}{1} \\ &=& 10 \cdot \frac{29}{2} \cdot \frac{28}{1} \\ &=& 10 \cdot \frac{29}{1} \cdot \frac{28}{2} \\ &=& 10 \cdot 29 \cdot 14 \\ &=& 290 \cdot 14\\ &=& 4060 \end{array}$

4,060