Asurf instructor has an initial fee of $12 and charges $8 per hour for lessons. explain how to determine what the y-intercept is and where it would be located on the graph.

There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?