A hacker is trying to guess someone's password. The hacker knows (somehow) that the password is 15 characters long, and that each character is either lowercase, an uppercase letter or a numerical digit. Assume that the hacker makes a random guess.
What is the probability that the hacker guesses the password on his first try? Enter your answer as a decimal or a fraction.
There are 26 possible lowercase letters, 26 possible uppercase letters, and 10 possible numbers (0-9).
26+26+10=62
That means there's a 1/62 chance that they get one letter right.
But there's 15 letters.
They're chance would decrease each time to get it exact.
1/62 divided by 15/1 =
1/832
So there is a 1 in 832 chance that the hacker guesses it correct first try with that information.
