- I am a 6 digit whole number.
- Half of my digits are 2's.
- Half of my digits are 1's.
- I am divisible by 3.
- I am an odd number.
- I am divisible by 9.
- My digits alternate.
- I am greater than 200,000.
- My hundreds digit is less than 2.
- My tens digit is 2.
Who am I?
Answer: I am 212,121.
The solution can be determined by clue 7.