A snail is stuck at the bottom of a 20-foot deep well. Each day it climbs up 3 feet, but each night while sleeping, it slides down 2 feet. On which day will the snail finally reach the top and escape?
Day 18
Each 24-hour cycle nets 1 foot of upward progress. After 17 days and nights, the snail is at 17 feet. On the 18th day, it climbs 3 feet, reaching 20 feet and escaping before nightfall.
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: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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