You are signing up to a website that requires you to create a username that is exactly 5 characters long. To create the username, you can use uppercase or lowercase letters (A-Z or a-z, 26+26 possible choices), numerical digits (0-9, 10 possible choices) and the symbols (*, # and @). note: suppose that the first 2 characters must be an uppercase letter and the last 2 characters must be a number. Your friend has already signed up, and he wants to see if you can guess his username correctly. He tells you that the first two characters are ”AD”, the 3rd character is a symbol, and the last two numbers are the same. You can make only one guess. You have no idea, so you make your guess at random using the information he gave you. What is the chance that your guess is correct?
You are signing up to a website that requires you to create a username that is exactly 5 characters long. To create the username, you can use uppercase or lowercase letters (A-Z or a-z, 26+26 possible choices), numerical digits (0-9, 10 possible choices) and the symbols (*, # and @).
note: suppose that the first 2 characters must be an uppercase letter and the last 2 characters must be a number.
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Your friend has already signed up, and he wants to see if you can guess his username correctly. He tells you that the first two characters are ”AD”, the 3rd character is a symbol, and the last two numbers are the same. You can make only one guess. You have no idea, so you make your guess at random using the information he gave you. What is the chance that your guess is correct?
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