A lily pad doubles in size every day. If it completely covers a pond in 30 days, on which day did it cover exactly half of the pond?
29
Since the lily pad doubles daily, it would cover half the pond on the day immediately before it is full, which is 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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