A lily pad doubles in size every day. On the 30th day, it covers the entire pond. On what day did it cover exactly half of the pond?
29
Since the lily pad doubles daily, whatever size it is on day 30, it must have been half that size the day before (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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