Tiger and Sheep brain teaser - interactive puzzle
← Brain TeasersTiger and Sheep
A hundred tigers and one sheep share a magic island with nothing but grass.
About Tiger and Sheep
A hundred rational tigers and one sheep on a magic island, where any tiger that eats becomes a sheep itself - solved by induction on parity.
The story sets three facts: a hundred tigers and one sheep share a magic island with nothing but grass; tigers would rather eat the sheep, but any tiger that does instantly becomes a sheep itself; and every tiger is perfectly rational and above all wants to survive. Then the question: with 100 tigers on the island, will the sheep be eaten?
Clicking through takes you to the answer builder at /brain-teasers/tiger-and-sheep/answer. You pick a tiger count - the choices are 1 through 8, then 100 - predict whether the sheep gets eaten or is safe, and write out your reasoning. A narrated walkthrough lives at /brain-teasers/tiger-and-sheep/breakdown.
Why quant interviews test this
This is a standard induction teaser: the interviewer is testing whether you instinctively reduce an intractable number to a base case, build a recurrence, and state the resulting invariant cleanly. The 100 in the problem is a bluff - candidates who engage with it directly, before n = 1, have already missed the point.
The Tiger and Sheep guide covers how scoring works, the strategy that wins, a worked example and the mistakes most players make.
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