Regarding this problem

None problem's answers don't seem correct.

If five digits are selected from a set containing {6, 5, 4, 3, 2, 1}, then the largest password is 66666 and the smallest is 00000. Therefore, the sum of all the possible passwords would be \(\sum _{ n=1 }^{ 66666 }{ n=\frac { 66666(66667) }{ 2 } =2222211111 } \).

What do you guys think?

## Comments

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TopNewestYou're incorrect.

Try listing down the first few smallest 5-digits that satisfy this condition and you will notice that not all 5-digit integers satisfy this condition. – Pi Han Goh · 1 year, 4 months ago

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– Andrew Tawfeek · 1 year, 4 months ago

Oh, you're right, it completely flew over my head! The second I read your reply and counted, "Well, 1, 2, 3, 4, 5, 6, 7... Wait a second...". Thank you for clearing this all up for me! :)Log in to reply