To find how many cards Dan started with, we can use the given context to determine equations:
His dog ate half of his collection, and now there are 32 cards left. This means that with the addition of the 5 new baseball trading cards, Dan had 64 trading cards. Now that we know he had 64, we can take away the 5 new baseball cards Dan purchased:
64 - 5 = 59
Therefore, Dan initially had 59 cards.
