Enigma 1113: Ten + ten = twenty
From New Scientist #2269, 16th December 2000
In the multiplications shown, where the combined products of multiplications (I) and (II) (both identical) equal the product of multiplication (III), each letter consistently represents a specific digit, different letters being used for different digits while asterisks can be any digit.
The multiplications in fact are not difficult to solve, and easier still if I told you that TEN is even.
How much is TWENTY?