i)
μ=np=100⋅0.1=10
σ=np(1−p)=100⋅0.1(1−0.1)=3
P(10≤X≤12)≈P(9.5≤Y≤12.5)=
=P(39.5−10≤Z≤312.5−10)=P(−0.17≤Z≤0.83)=
=0.7967−0.4325=0.3642
ii)
λ=np=10
P(X=k)=k!λke−λ
P(10≤X≤12)=P(X=10)+P(X=11)+P(X=12)
P(X=10)=10!1010e−10=0.1251
P(X=11)=11!1011e−10=0.1137
P(X=12)=12!1012e−10=0.0948
P(10≤X≤12)=0.1251+0.1137+0.0948=0.3336
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