SOLUTION: How many five-letter passwords can be made if no letters are repeated?
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Question 240223
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How many five-letter passwords can be made if no letters are repeated?
Answer by
solver91311(24713)
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26 ways to pick the first letter. For each of those ways, there are 25 ways to pick the second letter (one less because letters cannot be repeated). So 26 times 25 ways to pick the first two letters. Then 24 ways for the third letter and so on.
26 X 25 X 24 X 23 X 22.
You do the arithmetic.
John