What is $\dbinom{n}{1}$ for any positive integer $n$?
$\dbinom{n}{1}=\dfrac{n!}{1!(n-1)!}=\boxed{n}$.  Also, $\binom{n}{1}$ is the number of ways to choose 1 object out of $n$.  Since there are $n$ different objects, there are $\boxed{n}$ ways to do this.