Question

P(X = x) = k/x+1; where x=1,2,3
Evaluate k.

Answer 1

P(X=1)+P)X=2)+P(X=3)=1

$\frac{k}{1+1}+\frac{k}{2+1}+\frac{k}{3+1}=1$

$k(\frac{1}{2}+\frac{1}{3}+\frac{1}{4})=1$

$k\frac{13}{12}=1$

$k=\frac{12}{13}$