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Filling the Petri Dish
JP Morgan
A petri dish with bacteria doubles every minute. After an hour the petri dish is completely full. What portion of the petri dish is filled on 59th minute?
Answer
We know that at minute 60 the dish is full, it doubles every minute, and are asked for the portion filled one minute before. Well from minute 59 to minute 60 the bacteria amount doubled to fill the dish completely, so on minute 59 exactly one half of the dish is full.