don't understand

Question

The probability that Janice runs is 6/10. The probability that she runs and bicycles is 4/15. Find the probability that Janice bicycles, given that she runs.

Answer 1

Let A = she bikes and B = she runs

 

P(A|B) = P(A∩B)/P(B) = (4/15)/((6/10) = 4/9