A computer password consists of nine characters. Replications are allowed.
a. How many different passwords are possible if each character may be any lowercase letter or
digit?
b. How many different passwords are possible if each character may be any lowercase letter?
c. How many different passwords are possible if each character may be any lowercase letter or digit,
and at least one character must be a digit?
d. A computer is generating passwords at random, and each character is equally likely to be any of
the 26 lowercase letters or 10 digits. Replications are allowed. What is the probability that the
password will contain all letters?
e. A computer system requires the password to contain at least one digit. If nine characters are
generated at random from the 26 lowercase letters and 10 digits, what is the probability that they
will form a valid password?

Question

Quizplus · Accepted Answer

The Answer of A computer password consists of nine characters. Replications are allowed.
a. How many different passwords are possible if each character may be any lowercase letter or
digit?
b. How many different passwords are possible if each character may be any lowercase letter?
c. How many different passwords are possible if each character may be any lowercase letter or digit,
and at least one character must be a digit?
d. A computer is generating passwords at random, and each character is equally likely to be any of
the 26 lowercase letters or 10 digits. Replications are allowed. What is the probability that the
password will contain all letters?
e. A computer system requires the password to contain at least one digit. If nine characters are
generated at random from the 26 lowercase letters and 10 digits, what is the probability that they
will form a valid password?

A Computer Password Consists of Nine Characters