Squigly Squigly's Brain Teasers

Question:

A boat has a ladder that has 6 rungs that are 12 inches apart. The tide moves up 12 inches every 15 minutes, it is now one hour until high tide. The very edge of the ladder is in the water. How many rungs will be under water all the way at the highest point of high tide?

Answer:

The boat moves and up and down with the tide.

Try another Brain Teaser:

A man is lying dead in the middle of a clearing, in the middle of a forest, in the middle of a puddle, in a scuba suit. How did he die?