Question 1192580
add x*p(x)  for each
0+0.1+0.6+1.2=1.90 expected value.
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variance is squared dev. * prob. =(-1.9)^2*0.2+(-0.9)^2*0.1+(0.1)^2*0.3+1.1^2*0.4
=0.722+0.081+0.003+0.484
=1.29
sd=sqrt(V)=sqrt (1.29)=1.14