Area under normal curve S(-∞,p-3a)=0.0013 S(30,-2o)=0.0115 S(,+20)=0022820,lo=0.1359 S(-∞,p1o=0.1587S(41la,)=0.3413 S(-∞,p-0o)=0.5 30o+σ 1+3 20 1-30120101(计+04+20(+30 3210 2322 Area Under Normal Curve -3 -2 -  + +2 +3 S(-, -3)=0.0013 S(-, -2)=0.0228 S(-, -1)=0.1587 S(-, -0)=0.5 S(-3, -2)=0.0115 S(-2, -1)=0.1359 S(-1,  )=0.3413 -3 -2 -1 0 1 2 3 -3 -  + +3 -2 +2