An adventurous frog is at the bottom of a 30-foot well. Every day, it climbs up 3 feet, but every night while sleeping, it slips back 2 feet. On which day will the frog finally reach the top and escape the well?
The 28th day
On each of the first 27 days, the frog makes a net gain of 1 foot per day, reaching 27 feet by the end of day 27. On the 28th day, it climbs 3 feet up, reaching the 30-foot top immediately before it has a chance to slip back.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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