Hello, i'm a science student, trying to solve question regarding probability...can anyone help me....thanks! A bank security system uses password that consist of five letters followed by a single digit. 1. How many passwords are possible? 2.How many passwords consists of three A's and two B's and end in an even digit? 3.If you forget your password but remember that it has the characteristics described in part (2), what is the probability that you will guess the password correctly on the first attempt?