How about solving it in unary and not in binary? In binary system, each BIT can either be 0 or 1. But imagine a number system where each UIT can have only one value, say 2. So the number sequence goes like this: nothing=0, 2=1, 22=2, 222=3, 2222=4, 22222=5, and so on. So it's apparant that 2+2=22.