Leila purchased a pre paid phone card for $25. long distance calls cost 22 cents a minute using this card. leila used her card only once to make a long distance call. if the remaining credit on her card is $19.50 , how many minutes did her call last?

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?