<PRE><B>Question 869774</B>
{{{x=1}}},{{{P=5/10=1/2}}}
{{{x=2}}},{{{P=2/10=1/5}}}
{{{x=3}}},{{{P=3/10}}}
Cumulative
{{{x=1}}},{{{F=1/2}}}
{{{x=2}}},{{{F=1/2+1/5=7/10}}}
{{{x=3}}},{{{F=1}}}
Mean
{{{mu=1*(1/2)+2(1/5)+3(3/10)}}}
{{{mu=9/5}}}
Variance
{{{V=(1-9/5)^2*(1/2)+(2-9/5)^2*(1/5)+(3-9/5)^2*(3/10)}}}
{{{V=19/25}}}
Standard Deviation
{{{sigma=sqrt(V)}}}
{{{sigma=sqrt(19)/5}}}
</PRE>