anonymous one year ago 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 six baseball cards and nine football cards. Based on these data, what is, most likely, the number of baseball cards in the deck?

1. anonymous

24?

2. anonymous

@mathmath333

3. mathmath333

sry this looks higher level probablity than me

4. anonymous

ok

5. anonymous

@niels5x9 can you help

6. mathmath333

6x+9y=60 where x = bascket ball cards and y = football cards

7. mathmath333

so i think it simplifies to $$2x+3y=20$$ we have to check this number for x and y \begin{align}\{x,y\}=\{1,1\}\\ \{2,2\}\\ \{3,3\}\\ \{4,4\}\end{align}

8. anonymous

substitute x and y?

9. mathmath333

we see that $$\{4,4\}$$ satisfies hence $$4\times 6=24$$ basket ball cards, your answer is correct

10. anonymous

@mathmath333 thanks