PROBABILITY! PLEASE HELP! Samuel wants to create a password containing one, two, or three lowercase vowels followed by two digits. How many different passwords are possible? (Note: assume the letters "a", "e", "i", "o", and "u" are the ONLY vowels of the English alphabet.)

Using the fundamental counting principle, it is found that 15500 different passwords are possible.

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The fundamental counting principle states that if there are p ways to do one things, and q ways to do other thing, and they are independent, there are p*q ways to do both things.

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A similar problem is given at link

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