S1 - Probability

Stuck with part C?

I got 0.4 for part A and 0.4 for part b?

I know that if independent P(A n B) = P(A) x P(B)?
But I don't seem to be able to work out the intersection so I am guessing I might have to set up another equation? Thanks in advance

You can either adapt the formula for P(A u B), using what you know of independence


or also use the fact that independence implies

P(A'nB) = P(A')P(B)

etc.

Never thought about it that way. That is a lot simpler!
Using the first method what is the formula for P(A U B) when it comes to independence?