Study guides › Level 9 · If–Then

If–then

Level 9 · for questions like “If it rains, the picnic moves inside. The picnic didn’t move inside. What do we know?”

💡 The idea

“If A, then B” promises one thing only: whenever A happens, B happens. It says nothing about what happens when A doesn’t.

🪜 The steps

1. A happens → B happens.
2. B didn’t happen → A didn’t happen.
3. B happened → we can’t tell about A.
4. A didn’t happen → we can’t tell about B.

⚠️ Watch out

• The two traps are the last two: B could happen for another reason.

🎯 Try these

1. If a bell rings, the dog barks. The dog barks. Did the bell ring?
2. If it snows, school closes. School is open. Did it snow?

Answers: 1) Can’t tell 2) No

This guide is also in the 10LogicQ app: tap “📖 Study guide” after a puzzle.