Question

according to the general equation for conditional probablility if P(A upside down u B) = 5/9 and P(B)= 1/3 , what is P(A vertical line B)?

Answer 1

By definition of conditional probability,


`\mathbb P(A\mid B)=(\mathbb P(A\cap B))/(\mathbb P(B))`

Note that probabilities must always fall between 0 and 1, so
`\mathbb P(A\cap B)\le\mathbb P(B)`. But we have



`\mathbb P(A\mid B)=(\frac59)/(\frac13)=\frac53`

and this probability is greater than 1. So the question doesn't really make sense...