To set up a password for a computer account, the password must consist of two lowercase letters (a to z) followed by one capital letter (A to Z) followed by four digits (0,1,...,9). For the following two questions, you can leave the answers in multiplicative and fraction forms. (a) Find the total number of possible passwords. (b) Find the probability that the password contains at least one repetition in the letters or numbers. Note that the same letter in lowercase and in capital letter is considered as a repetition, for example, abA1234 is considered having a repetition in letter “a”.

To set up a password for a computer account, the password must consist of two lowercase letters (a to z) followed by one capital letter (A to Z) followed by four digits (0,1,...,9). For the following two questions, you can leave the answers in multiplicative and fraction forms. (a) Find the total number of possible passwords. (b) Find the probability that the password contains at least one repetition in the letters or numbers. Note that the same letter in lowercase and in capital letter is considered as a repetition, for example, abA1234 is considered having a repetition in letter “a”.

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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