A lily pad in a pond doubles in surface area every single day. If it takes 48 days for the lily pads to completely cover the entire pond, how many days did it take for the pond to be exactly half-covered?
47 days
Since the lily pads double in area every day, whatever area they cover on day 48 was half-covered on the previous day, which is day 47.
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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