Find the value of p in each of these probability distributions
x 5 7 9 11 13
P(X=x) p p p 0.12 0.04
x -2 0 1 3
P(X=x) 2/9 1/9 p 2/9
x -4 -1 2 5 8
P(X=x) 0.12 0.24 p 2p 0.07