Two marbles are drawn randomly one after the other without replacement from a jar that contains 4 red marbles, 4 white marbles, and 7 yellow marbles. Find the probability of the following events:
(a) A red marble is drawn first followed by a white marble.
(b) A white marble is drawn first followed by a white marble.
(c) A yellow marble is not drawn at all.
I understand how to do this with replacements but don't understand how to adapt the formula to no replacements