A hacker is trying to guess someones password The hacker kno

A hacker is trying to guess someone\'s password. The hacker knows (somehow) that the password is 10 characters long, and that each character is either a lowercase letter, (a, b, c, etc), an uppercase letter (A, B, C, etc) or a numerical digit (0, 1, 2, 3, 4, 5, 6, 7, 8, or 9). Assume that the hacker makes random guesses.

What is the probability that the hacker guesses the password on his first try?

Solution

There are 26 lowercase letters, 26 uppercase, and 10 digits. So, there are 62 characters to choose from for each of the 10 characters.

Thus, there are 62^10 ways to guess the password.

thus, the probability of getting it the first try is

P = 1 / (62^10) = 1.19147*10^-18 [ANSWER]