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Mission 15 of 16

Number Reasoning

📋 What it is

Many puzzles hide number patterns — powers of two, GCDs, remainders — that reveal the answer or prove it impossible.

🗣️ Coach says

Behind the pegs and jugs, the same number ideas keep appearing: powers of two (Hanoi), GCD (water-pouring), remainders and parity (impossible scrambles). Spotting the number underneath turns a “try everything” puzzle into a “I know the rule” puzzle.

🧠 Memory hook

Look under the puzzle for the number rule — powers of 2, GCD, or remainders.

😂 Giggle

Why did the puzzler work backwards?
Because starting from the answer sometimes reveals the way!

😲 Whoa!

The same “remainder” idea (modular arithmetic) that solves clock puzzles and the water-jug puzzle also secures your online passwords — one number idea, everywhere.

✅ Quick check: Hanoi uses powers of two and water-pouring uses GCD. What does that tell you about puzzles?

Say your answer out loud first — then reveal.

🧪 Try it! (2 minutes)

Take any puzzle you’ve met and ask: is there a number rule hiding in it (doubling? even/odd? remainders?)?

⭐ Do the round to earn your star →
🤸 Brain break: Number-hunt: mime lifting a “puzzle lid” to peek at the number rule underneath.