A lily pad doubles in surface area every single day. If it takes 48 days to cover an entire pond, how many days does it take to cover exactly 25% of the pond?
46 days
Because the lily pad doubles each day, working backward shows that on day 47 the pond is half covered (50%), and on day 46 it is one-quarter covered (25%).
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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