a box contains 10 dimes , 15 nickles and 4 pennies. We draw 2 coins at random (without replacement)

Let X represent the amount (in cents) that we draw out of the box.

Give (explicitly) the probablity mass function for X.


So the sums or amount i can have of X in cents is (2,6,10,11,15,20)

so the probability of getting 2 cents would be the probability of getting 2 pennies, so (4/29)(3/28)= 3/203

X(6) = P(1,5) = (4/29)(15/28)=15/203


So would PMF look something like

px(X)= {3/203 x=2
15/203 x=6

etc?

I am not really sure if i am on the right track?