Math CentralQuandaries & Queries


Question from Godryk, a student:

I am the smallest 7-digit odd number. my ones digit is the sum of my thousands, and ten thousands digits. What number am I?


Here is what the number will look like. I put u for the units digit (the ones digit), t for the thousands digit and T for the ten thousands digit.

7 digits number

Since this is a 7 digit number the leading digit can't be zero. I want the number to be as small as possible so the leading digit must be 1.

7 digits number

The only other requirements involve T, t and u so I can fill in the remaining 3 digits any way I want but keeping the number as small as possible. Thus the 3 remaining digits must be 0.

7 digits number

The number is odd so u must be odd.

Can you complete the number?


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