Question

If a discrete random variable has the probability mass function as then the value of K is _______

X	0	1	2	3
P(x)	k	3k	6k	2k

(a) 1/11

(b) 1/12

(c) 2/13

(d) 4/9

Answer 1

(b) 1/12

k + 3k + 6k + 2k = 1

⇒ 12k = 1

⇒ k = 1/12