Posted by edwin on .
use the clues to find the 7th digit mystery number.
* it is between 7 and 8 million
* it contains all of the digits greater than 1 and less than 8
* the hundred thousands digit is 3
* the ten thousands digit and the thousand digits are the same
* the tens digit is greater than the hundreds digit.

math 
PsyDAG,
Using the first and third clues, the number is 7,3xx,xxx. From the second clue, the remaining numbers are 6, 5, 4, 2, with one of them being repeated (fourth clue).
However, I cannot find a definitive way of placing the the remaining four numerals. Several arrangements could fit, for example:
7,366,245
7,355,462
7,344,256
Have you omitted some information?
I hope this helps. Thanks for asking. 
math 
Sam,
7,344,256