A certain roller coaster has 3 cars,and a passenger is equally likely to ride in any 1 of the 3 cars each time that passenger rides the roller coaster. if a certain passenger is to ride the roller coaster 3 times, what is the probability that the passenger will ride in each of the 3 cars? 本人概率都忘的差不多了，哪位NN能给解释一下？ | 
