Linear inequality problem.. Help?

What is the greatest integer that is a solution to the inequality $12 > \frac{x}{2} +1$?

$\begin{array}{|rcll|} \hline 12 > \dfrac{x}{2} +1 \quad & | \quad -1 \\\\ 11 > \dfrac{x}{2} \quad & | \quad \cdot 2 \\\\ 22 > x \quad & | \quad \cdot 2 \\\\ x < 22 \\ \hline \end{array}$

The greatest integer is 21