She said it as a statement wearing the clothes of a question. Emily heard the clothes.
“No,” Emily said. “A remainder has to be smaller than what you’re dividing by. If it isn’t, you haven’t finished dividing. You could have a remainder of zero, one, two, three, four, five, or six. Not twelve. Twelve would mean there were still sevens left to take out. So the second line, as you copied it, wasn’t a hard problem. It was a broken one. That’s why I said one number.”
Caleb looked as if he had been struck lightly with a fact. Color came into his face, not the ear-color of shame but the flush of a mind changing direction. He pulled the worksheet back toward himself. He did not erase yet. He looked up at her with a hope so naked she nearly looked away from it, the way you look away from a person changing clothes.
“So if it’s two,” he said, “I can do it. I was trying to do an impossible thing. I thought I was stupid.”
“You were careful,” Emily said. “Careful in the wrong room. It happens.”