This reminds me of my youngest in grade 1 in tears at his math homework.
What is 1 + 1?
He scrawled 2.
How did you arrive at this answer?
"I just added them. But that's not what the teacher wants. Waah!"
I tried for 10 minutes to tease out the mental process from him, but he was well beyond using representational systems to add numbers. At this point, he just *knew*. Furthermore, my pathologically honest child could not lie at that age, so pretending he put two items together and counted them was right out.
So I pulled out my first year math text which was mostly "God gives you zero and the successor function and 450 pages from now we prove calculus", and copied the appropriate paragraph or two.
Teacher never said anything about it, and I didn't see another quite so insane question that year.