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Puzzle image: made for aglena.
A sun, a cloud and a raindrop each stand for a whole number. Raindrops count one by one, so a tile with three drops is worth three raindrops. Three equations give you everything you need. The last line looks familiar, but look closely before you add it up.
The puzzle
- Cloud + Cloud + Sun = 15
- Sun + (3 raindrops) + (3 raindrops) = 19
- Cloud + (3 raindrops) = 10
What is Sun × Cloud + (2 raindrops)?
Show hint
Use the third equation to write the cloud in terms of the raindrops, then put that into the first equation. Together with the second equation, you’ll have just one unknown left.
Show answer
Answer: 32. The sun is 7, the cloud is 4 and each raindrop is 2.
Puzzle image: made for aglena.
- Call one raindrop D. Each three-drop tile is worth 3D. From the third equation, Cloud = 10 − 3D.
- Put that into the first equation: 2 × (10 − 3D) + Sun = 15, so Sun = 6D − 5.
- The second equation says Sun + 6D = 19. Swap in Sun = 6D − 5 and you get 12D − 5 = 19, so 12D = 24 and D = 2.
- That makes each three-drop tile worth 6, the cloud worth 10 − 6 = 4, and the sun worth 15 − 4 − 4 = 7. Check: 7 + 6 + 6 = 19.
- Now the last line. Multiplication comes first, and it’s already on the left: 7 × 4 = 28. The final tile holds only two drops, so it’s worth 2 × 2 = 4. Total: 28 + 4 = 32.
The trap is the last tile. If you read it as the same three-drop tile from the clues, you’d add 6 and get 34. Counting the drops gives the right answer.
