If you write out the numbers from 1 to 5000 in American English (e.g., THREE THOUSAND EIGHT HUNDRED SEVENTY-THREE), it turns out that only one of them has a unique number of characters.

Which is it?

Spaces and hyphens count as characters.

I have solved the problem analytically, -

but only now   I have found a nice and concise explanation how the number 3000 can be derived by logical process .

Please see the official solution.

Posted by Ady TZIDON on 2016-03-26 11:16:05