Why Aeroplane windows are round?

What came first, the chicken or the egg?

The picture shows the dice results in each couple of throws. If they are actually following a pattern, can you find out the missing one?

They are three errirs in this question. Can you find them?

Find the number of squares in the below-given picture.

You are given with the following sum. Each of the letters can be decoded as a digit. If we tell you that D = 5, then can you solve it entirely?

DONALD
+GERALD
=ROBERT

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

During an experiment, a guy throws a bouncy ball from a 100 feet tall building. The ball has a specific characteristic. Every time it hits the ground, it bounces up halfway.

How many bounces do you think the ball will make before it comes to a stop ?

I have teeth but i don't bite. Who Am I ?

I am a prime number.
The double of myself is equal to the square of me.

which number am I?