A lily pad doubles in surface area every day. If it takes 48 days to completely cover a pond, on which day was the pond exactly half-covered?
47
Because the lily pad doubles in size daily, it was at 50% capacity on the day directly preceding full capacity (48 - 1 = 47).
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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