A woman lives in a skyscraper thirty-six floors high and is served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

Spot 5 differences in two Christmas tree below:

How many triangles are there on the puzzle below?

Sally lives in a place where six months of the year is mild summer and the temperature drops significantly the other six months. She owns a lake where there is a small island. She wants to build a house on the island and needs to get materials there. She doesn’t have a boat, plane, or anything to transport them to the island. How does Sally solve this problem?

Can you find out a way through which you can make five squares out of the given figure by moving just six match sticks?

What has many teeth, but cannot bite?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?