If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

While preparing the table for dinner, wife came up with an idea to tease his mathematician husband. She asked her husband to pick nine toothpicks and make ten without breaking any toothpick.

The husband was also smart and did it within seconds. How ?

Let's play a word game. Following are some meaningless words that can be completed by adding random letters on either side of the word.

For example, the word "rdo" can be formed into "pardon".

Using the same technique, can you complete the given words?
ecalc
airb
rinci
tibac
uidel
gorit
igna
eyho

What makes this number unique: 8,549,176,320?

There are three houses in a straight row. One is red, one is blue, and one is white. The red house is left of the middle. The blue house is right of the middle. Where's the white house?

Move three sticks of the spiral below to form a square.

There is a family that live in a round house. The two parents go out for a movie and leave a babysitter to watch their son. They come back and the kid was not there. Some one kidnapped him. The maid said she was cleaning in a corner. The cook said he was making pizza. The babysitter said she was getting a board game. Who kidnapped him.

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

How can you take 2 from 5 and leave 4?