A lily pad doubles in size every day. If it covers a whole pond in 30 days, how many days did it take to cover half of the pond?
29 days
Since the lily pad doubles daily, it would be half the size on the day right before it covers the entire pond. 30 - 1 = 29 days.
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: Easy. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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