Can someone help me please?

Let $\frac{m}{n}$ be a fraction, where $m$ and $n$ are positive integers. Consider the operation defined by replacing $\frac{m}{n}$ by $\frac{m+1}{n+1}$ and then writing the result in lowest terms. For example, applying this operation to $\frac{5}{14}$ would give $\frac{2}{5}$. How many times must this operation be repeatedly applied to $\frac{1}{2005}$ before we obtain $\frac{2004}{2005}$.