Question

Consider X is a normally distributed variable with mean = 20 and standard = deviation o = 5. Find a) P(20 < x 22) c) P(12​<×<23)

Answer 1

.1554

.6709

Explanation:

p(20<x<22)= p(x<22)-p(x<20)

p(x<22)=(22-20)/5= .4 = .6554

p(x<20)= (20-20)/5= 0 = .5

.6554-.5= .1554

p(12<x<23)= p(x<23)-p(x<12)

p(x<23)= (23-20)/5= .6= .7257

p(x<12)= (12-20)/5= -1.6 = (1-.9452)= .0548

.7257-.0548= .6709