Brady has a card collection with 64 basketball cards, 40 football cards, and 32 baseball cards. he wants to arrange the cards in equal parts. with only one type of card in each pile

break down the numbers 64, 40, and 32 to find a common number.

64
32
16
8
4
2

40
20
10
8
5

32
16
8
4
2

In all three, there is a common number of eight.
Therefore (answer):

There would be 8 cards in each pile.
8 piles of basketball cards, 8 cards per pile.
5 piles of football cards, 8 cards per pile.
4 piles of baseball cards, 8 cards per pile.

I hope I explained this good enough. Please comment with any questions you may have on how I got this answer.