Welcome to the Island of Knights, Knaves, and Sir Mix-a-lot! There are a few things you should know about this island:

- Knights
*always*tell the truth - Knaves
*always*lie - There is exactly one Knight named “Sir Mix-a-lot”. Like every other knight, he cannot lie.
- This island is one of a chain of islands containing knights and knaves, each one having its own quirk.

Today we are on a very interesting island, the Island of Day Knights and Night Knights. Day knights always tell the truth during the day, but lie at night. Night knights tell the truth at night, but lie during the day. Annoyingly, they all live in structures built underground, so it is impossible for visitors at any given moment to know whether it is daytime or nighttime on the surface.

You are walking along an underground street when you happen upon a resident of the island. You have no idea what time it is, being underground and all, but you’d like to know if it’s daytime or nighttime. How many questions do you need to ask the resident to figure it out?

#### Solution:

You can do it with one question, “Are you a day knight?” A “Yes” response means that it is daytime, and a “No” response means it is night. See if you can figure out why. I’ll demonstrate why in my next post, which I will link to here later on.