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# Rat And Poison Puzzle

There are 1000 wine bottles in your possession, but unfortunately, one of them is poisoned. To identify the poisoned bottle, you plan to use 10 rats as your test subjects. However, you must act quickly, as the poison takes effect one hour after consumption. Therefore, you only have one chance to conduct your experiment with the rats to find out which bottle is deadly.

## Rat And Poison Puzzle solution

To determine which bottle is poisoned, you can label each bottle from 1 to 1000, then assign each bottle to a unique binary number from 0 to 999 in binary form.

For example, bottle 1 would be labeled 0000000001 in binary, bottle 2 would be labeled 0000000010, and so on until bottle 1000 is labeled 1111101000.

Next, assign each rat to a unique bit position in the binary number, for example, Rat 1 can represent the first-bit position (least significant bit), Rat 2 can represent the second-bit position, and so on until Rat 10 represents the tenth-bit position (most significant bit).

Then, for each bottle, you can feed the rats the wine from the bottle, and based on which rats die, you can determine the binary number representing the poisoned bottle.

For example, if rats 1, 2, and 4 die, you can determine that the binary representation of the poisoned bottle is 0000000111, which in decimal is bottle number 7.

By using this method, you can determine which bottle is poisoned using only 10 rats and one test, as each rat represents a unique bit position in the binary number system, allowing you to uniquely identify each bottle.

The interviewer can add some extra details to confuse you such as “A rat dies after one hour of drinking the poisoned wine”. This puzzle tests your critical thinking, logical reasoning, and problem-solving skills, as you must devise a strategy to determine the poisoned bottle in the shortest time possible.