A patch of lily pads in a lake doubles in size every single day. If it takes 48 days for the patch to completely cover the entire lake, on what day was the lake exactly 25% covered?
Day 46
Because the patch doubles every day, working backward from day 48 (100% covered) means day 47 was 50% covered, and day 46 was 25% covered.
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: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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