put two and two together

She appears frustrated that authorities did not put two and two together sooner that criminal groups were using this as a front: "The entire economy here is stagnant. Yet one item that has increased in exports is bananas. So, two plus two equals four."

While this might have come as a complete surprise to most parents, Clare quickly put two and two together.

"I bumped into William McNamara in Blackpool looking at the big dip of a wooden coaster there. I put two and two together immediately," he said.

And will Belinda, who spots Greg sitting across the restaurant, put two and two together?

“It was such a small ad, I don’t think anyone put two and two together,” a source told Variety.