Ryan's Solution
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[2] [2] If the units digit cannot be a multiple of 3, the only digit so far
- - that is not allowed in the units digit is 6, as 3 or 9 are
[4] [4] already not allowed as it is an odd number. The tens digit can't
- - be double the units digit, so it can't be 84 or 42. If the tens
[6] [6] digit has to be bigger than the units one, it can't be 24 or 28.
- - Altogether, the impossible solutions are: 84, 42, 24, 26 and 28.
[8] [8] Therefore, there are only two possible solutions: 62 and 64.
[_?_][_?_] As 62 is not in the list of numbers they give you, the answer is 64.
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[Answer:64]
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