$\begingroup$How many 6 digits number can be generated using digits 0-9 with repetition of any digit?
Few Examples: 111111 122222 123333 123456 324222
$\endgroup$32 Answers
$\begingroup$Hint:
how many are the numbers between $100000$ and $999999$ ?
$\endgroup$0$\begingroup$By the Rule of Product, they are $9\cdot 10^5$ if you want that the first digit is different from zero. They are $10^6$ if you allow that the first digit can be zero.
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