On a 75 feet rope, A snail crawls up 5 feet during the day and slides down 4 feet in the night. How many days/nights will it take for the snail to completely crawl up the 75 foot rope?
Everyday the snail gains 5-4 = 1 foot BUT toward the end the snail will be at the top before sliding back down:
on day 71 before starting the climb, snail will be at 70 ft...... then climbs up 5 ft and is at the top......71 days
