Find the next number in the sequence

1, 2, 6, 21, 88, __?

In the figure, you can see nine stars. What you have to do is connect all of them by using just four line and without lifting your hand i.e. in a continuous flow.

Find the 8 in the below-given Image.

Why Aeroplane windows are round?

The below given figure comprises of a pattern through which you can determine the missing letter. Can you push your mind to find the pattern and add the missing letter?

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?

In the given picture, in how many ways can you read the word "Tiger"?

Can you move 2 matchsticks to form four equal sized squares.

Can you make the below equation true by using any three numbers from "1, 3, 5, 7, 9, 11, 13 and 15"?

( ) + ( ) + ( ) = 30

Keyboard words are not in alphabetical order, Why?