A snail climbs up a 20-foot wall. Each day it climbs 4 feet, but each night it slips back 2 feet while sleeping. On which day will the snail finally reach the top of the wall?
Day 9
On days 1 through 8, the snail gains 2 net feet per day, reaching 16 feet by the end of Day 8. On Day 9, it climbs 4 feet right away, reaching 20 feet (the top) before it has a chance to slip.
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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