A botanist grows a rare lily pad in a pond that doubles in surface area every single day. If it takes 30 days for the lily pad to cover the entire surface of the pond, how many days did it take to cover exactly half of the pond?
29 days
Since the lily pad doubles in size every day, whatever area it covers on day 30, it covered exactly half of that area on day 29.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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