A riddle

[AFO]

A frog falls into a 50 feet dry, but, moist water well and goes all the way down to the bottom.
This frog manages to leap up 3 feet during a day, and unfortunately it slips back two feet during the night.
Can you tell me how many days it would take this frog to get to the surface, if it will get there at all?

I'll post the answer next Monday.

[Diri]

The 48th day it will be able to climbe out of the well...

Because the 47th - it will reach the top - BUT at night it will slip another two feet back - so it will slip back to 48 feet (counting from the bottom) - and that day (the 48th) will be able to make that EXTRA jump needed to jump OUT of the well!

[missIndependent]

[AFO]

defined the surface as the zero dept or the edge of the well. With this definition, I came up with 48 days. Here is my rational:

Assumptions:
- Goal to get to the edge of the well.
- A cycle consists of one day followed by a night (24 hrs).
- Cycle one starts when the frog hits the bottom. And I assume it’s the beginning of the day.

The logic:
By the end of the first cycle the net up movement of the frog is one foot (first 3 feet up during the day, then 2 feet down during the night).
By the end of the 47th cycle, the total of the up movement would be 47 feet.
At the beginning of the 48 cycle, the frog starts climbing up and by the end of the day (before night start) climbs 3 feet and this would bring it to the edge or the surface and she is there.

Discussion:
- One might say that it’s actually 47.5 days (cycles).
We can also argue the getting up to the edge its not enough and the frog would not be able to stay there and would fall back again, therefore, it needs the 49th day to get out and stay.
Depending how to look at the process and how realistic we get, the correct answer could be different.

Enjoy the laughter of these little ones.

http://www.killsometime.com/Video/Files ... Babies.wmv

http://www.killsometime.com/Video/Files-1952196/Laughing-Babies.wmv