Question

Let A and B events in sample space such that:
P(not A and not B) = 0.20
P(A) = 0.6
P(A|not B) = 0.5
Find P(B), P(not A|B)

Answer 1

What I tried doing is since P(not A and not B) = 0.20 then 0.20 = 1 - P(A or B) which implies P(A or B) = 0.8, so then now since P(A|not B) = 0.5 then implies P(A and B) = 0.1, so P(B) = 0.3 and P(A|not B) = 0.5 but the answers are P(B) = 0.4 and P(A|not B) = 0.5, how come P(B) = 0.4 and not 0.3?

Answer 2

if i see it right