A lily pad doubles in size every day. If it takes 30 days to cover the entire pond, how many days did it take to cover exactly half the pond?
29 days
Since the lily pad doubles daily, on the day before it covers the whole pond (day 30), it must have covered half the pond (day 29).
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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