Atividade

Calculos utilizando a tabela normal

X ~ N(500,300)

a) Pr(X<500)

Z=(500-500)/300= 0

Pr(x<0)

Pr= 50%

b) Pr(400<X<710)

Z1=(400 - 500)/300= -0.3333333

Z2=(710-500)/300= 0.7

Pr(-0.3333333<x<0.7)

Pr= 0.12552 + 0.25804

Pr= 0.38356

c) Pr(330<X<450)

Z1=(330-500)/300= -0.1666667

Z2=(450-500)/300)=-0.5666667

Pr(-0.5666667<x<-0.1666667)

Pr= 0.21226-0.06356

Pr= 0.1487

Y ~ N(100,20)

a) Pr(50<Y<70)

z1= (50-100)/20

z2= (70-100)/20

Pr(-2.5<Y<-1.5)

Pr = 0.49379 - 0.43319

Pr = 0.0606

b) Pr(105<Y<110)

z1= (105-100)/20

z2= (110-100)/20

Pr(0.25<Y<0.5)

Pr =0.19146 -0.09871

Pr = 0.09275

c) Pr(Y>75)

Z= (75-100)/20

Z= -1.25

Pr(Y>-1.25)= 0.39435

Pr = 0.39435 +0.5

Tabela Utilizada