Answer:
14.2, 16.96
Step-by-step explanation:
given is a probability distribution of X
X is discrete taking values as 7, 11, 15 and 19
X 7 11 15 19 total
p 0.10 0.35 0.20 0.35 1
x*p 0.7 3.85 3.0 6.65 14.20
x^2*p 4.9 42.35 45 126.35 218 .60
Hence mean = sum of prob (x) = 14.20
[tex]E(x^2) =218.60[/tex]
[tex]Var(x) = E(x^2)-{E(x)}^2\\= 218.60-14.20^2\\= 16.96[/tex]