Question 350747
a) {{{P(0)+P(1)=0.2+0.62=0.82}}}
.
.
.
b)
{{{E=sum(x*P(x),x=0,3)}}}
 {{{E=0(0.2)+1(0.62)+2(0.13)+3(0.05)=1.03}}}
.
.
.
c) {{{SD^2=sum((x-E)^2*P(x),x=0,3)}}}
{{{SD^2=(0-1.03)^2(0)+(1-1.03)^2(1)+(2-1.03)^2(2)+(3-1.03)^2(3)=0.5291}}}
{{{SD=0.7274}}}