Roberto wants to display his 18 sports cards in an album. some hold 2 cards and others hold 3 cards. how many different ways can roberto display his figures?

3 is an odd number, so we need an even number of sets of 3 cards because 18 is an even number.
So we need 0, 2, 4 or 6 sets of three.
0 2-card + 6 3-card, 3 2-card+4 3-card, 6 2-card+2 3-card, 9 2-card+0 3-card. There are only 4 combinations:
(2-card, 3-card)=(0,6), (3,4), (6,2), (9,0).

2 2/3, 2 1/4, 2 1/5, 2 1/8

step-by-step explanation:

answer to ttm