For the first letter drawn, there are no conditions/restrictions we need to consider. So, the number of ways to draw an i is:

For the second draw, the i is not replaced. That means, we've shrunk the sample space because we're dealing with less elements for the second draw. Firstly, one i disappears since we picked an "i" and there are 10 elements left, not 11.
Thus, to draw the second i, we have:

