How do you solve this factorial problem

Question

$$x!=\frac{(10!)!}{10!}$$

I’m not sure how to do this and me, a physics major, and my roommate, a math major, can not figure this out. I’m sure there’s a very simple solution that is obvious once you know it but I just dont

Thanks for the help

Answer 1

Notice $x! = \frac{(10!)!}{(10!)} = (10! - 1)!$ so $x = 10! - 1$.