Event A: a customer asks for help. Event B a customer makes a purchase. We know: p(B) = 0.2 and p(A) knowing that he has asked for help is 75%. What is the probability of a customer to ask for help and make a purchase?

If we right down all we have here we get:P(A) = X P(B) = 0.2 P(AIB) = 0.75 (P(A) knowing B). And we are looking for P(ANB). We have to use the formula of P(AIB) = P(ANB)/P(B). If we rearrange the equations, we get isolate P(ANB) = P(AIB) * P(B) which gives us what we a looking for.P(ANB) = 0.75 * 0.2 = 0.15