What is the next number in this series?

4,12,84,3612....

Why Aeroplane windows are round?

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

You have 1023 apples and 10 bags. You have to distribute these apples in these 10 bags in any way you choose. But when I ask for a certain number of apples you have to give them in terms of bags without transferring the apples from other bags. How do you distribute the apples?

Decode the movie name from the below picture?

Find The Next Number in this series.
1, 2, 6, 42, 1806 ?

The barber of Town shaves all men living in the town. No man living in the town is allowed to shave himself. The barber lives in that town. Who then shaves the barber of the town?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

Replace the (?) with the correct mathematical signs to make the expression equal to 59.

18 ? 12 ? 4 ? 5 = 59

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

which number am I?