Possibilties before rules:
UNITS: 1 2 3 4 5 6 7 8 9
TENS: 1 2 3 4 5 6 7 8 9
Rule 1: Digits are greater than 3, so new possibilities are
UNITS: 4 5 6 7 8 9
TENS: 4 5 6 7 8 9
Rule 2: Sum of digits greater than 15, (i.e. 16 or more),
but we know unit digit cannot be more than 9,
so new possibilities are
UNITS: 7 8 9
TENS: 7 8 9
combined in these possible options,
79. 88, 89, 97, 98, 99
Rule 3: The number is not odd, so new possibilities are
88, 98
Rule 4: The tens digit is greater
It must be 98
Regards - Ian
