Permalink Submitted by Anonymous on April 17, 2016

I've been trying to think of a method to decompose a number into a number which, added to its reverse, equals that first number. For example 685 decomposes into 392+293, but I only know that because I started with 392 arbitrarily. Do you or anyone know of a quick sure method to start with a number like 685 and find 392?

## Reversing the summing of reversibles

I've been trying to think of a method to decompose a number into a number which, added to its reverse, equals that first number. For example 685 decomposes into 392+293, but I only know that because I started with 392 arbitrarily. Do you or anyone know of a quick sure method to start with a number like 685 and find 392?

Chris G