Find the constant k from the joint probability function of two random variables?
The joint PF of two discrete RVs X and Y is given by:
PXY(x,y) = k(2x+y) x=1,2; y=1,2
= 0 otherwise
How do I find the constant k?
I got k to be 1/18, but I don't know if that's right
- kbLv 76 years agoFavorite Answer
Remember that the sum of all (nonzero) probabilities should equal 1.
So, we need
P(1, 1) + P(1, 2) + P(2, 1) + P(2, 2) = 1
==> 3k + 4k + 5k + 6k = 1
==> k = 1/18.
I hope this helps!