Assume deck contains 4 A, 5 face, 13 non-face cards; 3 drawn

[Angela123]

Assume that a deck of cards contains 4 aces, 5 other face cards, and 13 non-face cards, and that you randomly draw 3 cards. A random variable Z is defined to be 3 times the number of aces plus 2 times the number of other face cards drawn.

Complete the probability density function. Find the probability for each value of x. I found out the values of x are 0, 2, 3, 4, 5, 6, 7, 8, 9 but that was by pure luck. Can anyone explain where those numbers came from? I know how to find the probability of 3 aces, etc., but I don't know which probability goes with which value of x.

 

[Deleted member 4993]

Re: random variables

Assume that a deck of cards contains 4 aces, 5 other face cards, and 13 non-face cards, and that you randomly draw 3 cards. A random variable Z is defined to be 3 times the number of aces plus 2 times the number of other face cards drawn.

Complete the probability density function. Find the probability for each value of x. I found out the values of x are 0, 2, 3, 4, 5, 6, 7, 8, 9 but that was by pure luck. Can anyone explain where those numbers came from? I know how to find the probability of 3 aces, etc., but I don't know which probability goes with which value of x.

duplicate post:

http://www.jiskha.com/display.cgi?id=1223584175

Please tell us the definition of 'x' - whose values you found by luck.

Please a tell us why does not the set of numbers for 'x' - does not have any '1'?

Please also tell us - why is the maximum number in the set is '9'?

By the way - those are correct observations - but I want you to think about it a bit and explain.