Answer :
Day Up Down Deep at the end of the day
1 5 2 50 - 3 = 47
2 5 2 50 - 6 = 44
3 50 - 9 = 41
4 50 - 12= 38
...
15 50 - 15*3 = 5
16 5 5 - 5 = 0 ´this day it leaves when goes up 5 feet and so does not go down the 2 feet
The snail will leave on the day 16th
1 5 2 50 - 3 = 47
2 5 2 50 - 6 = 44
3 50 - 9 = 41
4 50 - 12= 38
...
15 50 - 15*3 = 5
16 5 5 - 5 = 0 ´this day it leaves when goes up 5 feet and so does not go down the 2 feet
The snail will leave on the day 16th