Question

Jamie has a deck of 60 sports cards, of which some are baseball cards and some are football cards. Jamie pulls out a card randomly from the deck, records its type, and replaces it in the deck. Jamie has already recorded three baseball cards and nine football cards. Based on these data, what is, most likely, the number of baseball cards in the deck? 12 15 24 30

Answer 1

The number is most likely 15 because if you one recorded 3 baseball cards and 9 baseball cards it would be most reasonable to have it be 15

Answer 2

15

Explanation:

The proportion between baseball and football cards is 3 to 9, which is equivalent to 1 to 3, that means if you pull out a card you have a probability of 1/4 to get a baseball card and 3/4 a football card.

60/4 = 15, then instead of 1/4 we can say 15/60 (= 1/4 * 15/15) and instead of 3/4 we can say 45/60 (= 3/4 * 15/15). So, based on these data, there are 15 baseball cards and 45 football cards.