Traditional Culture Encyclopedia - Weather inquiry - Mathematical weather problem

Mathematical weather problem

Note that event A: A is sunny and B: B is sunny. As we all know:

P(A)=7/ 10，P(B)=2/5，P(AB)=3/ 10，

P(Aˉ)= 1-P(A)=3/ 10，

P(A∪B)=P(A)+P(B)-P(AB)=4/5。

P(AˇBˇ)= P[(A∪B)ˇ]= 1-P(A∪B)= 1/5。

P(b\ | a\)= P(a\b\)/P(a\)= 2/3。