Insight · ★★★★☆ · ~8 min
1000 Bottles, 10 Tasters
One poisoned bottle among 1000, ten prisoners, 24 hours. The answer hides in binary.
by MindYourPuzzle
A legendary "aha" puzzle from tech and quant interviews — the moment it clicks, you'll never see numbers the same way.
The king's cellar has 1000 identical bottles of wine. Exactly one has been poisoned. The poison is extraordinary:
- A single drop — no matter how diluted — is lethal.
- It works slowly: symptoms (and death) appear after about 24 hours, with no earlier warning.
The king's feast is in 24 hours, and he needs to find the poisoned bottle by then. He has 10 prisoners he's willing to use as tasters, and he can make each prisoner sip from any combination of bottles.
What is the maximum number of bottles you could screen with just 10 testers in one round — and how?
(Answer with the largest number of bottles 10 testers can handle.)
bottles
Hints