Counting the 3-of-a-kind hands requires some care.
Question 24: Explain what is wrong with the following reasoning:
There are 52 ways to select the first card that is a part of the 3-of-a-kind. . True!
Then there are ways to pick the other two cards to make up the 3-of-a-kind. . Yes!
Finally, there are ways to pick the other two cards. . ← Here!
Picking any two of the other 48 cards, we could get a Pair, forming a Full House.