Frog paradox.
Level
pending
A frog is stuck at the bottom of a 30 foot well. Every hour, it climbs 3 feet and then drops 2. How long does it take for the frog to get out the well?
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1 solution
The climb is equivalent to 3 − 2 = 1 step up, so until the height of 3 0 − 3 = 2 7 feet, it reaches the 2 7 feet mark by 1 foot each, then it takes the leap of 3 feet to get to the peak, in a total of 2 7 + 1 = 2 8 steps.