Place means the ones place, tens place, hundreds place etc. The places increase from right to left, so this number has increasing digits from right to left.
54321 - the digits add to 15.
Any number with one larger digit is an answer to this problem.
64321 - the digits add to 16 > 15
75432 - digits add to 20 > 15. That works too.
There are many possible answers.
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