Question

In a class containing 18boys 22 girls one student is absent find the probability the absent, student boy

Answer 1

total students = total boys + total girls
= 18+22
=40
probability of absent student boy =18/40
=0.45

Answer 2

let p(e1)=18/40
p(e2)=22/40
a=absent student
p(a|e1)=1/18p(a|e2)=1/22
p(e1|a)=1/2