Medium
How many three digit numbers can be formed using the digits 2, 6, 0 (without repetition)?
Explanation
Explanation
Total arrangements of 3 digits = 3! = 6, but numbers cannot start with 0. Numbers starting with 0 (invalid): fixing 0 first, remaining 2 digits arrange in 2! = 2 ways. Valid 3-digit numbers = 6 - 2 = 4.
PRO TIP
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