Solve the following series:
AZ, GT, MN, __, YB

On a magical land of Mexico , all the animal in the land are rational.

There are 10 tigers and one goat.
Tiger can eat goat but since it's a magical land , the tiger who eats the goat , turns into goat and then can be eaten by the remaining tiger(s).

If we leave them for some time then how many goat and tiger will be there , when we come back ?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

What's the next in the series?

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?

What number do you get when you multiply all of the numbers on a telephone's number pad?

Complete the table series riddle by finding the number that can replace "??".

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

The first box has two white balls. The second box has two black balls. The third box has a white and a black ball.

Boxes are labeled but all labels are wrong!

You are allowed to open one box, pick one ball at random, see its colour and put it back into the box, without seeing the colour of the other ball.

How many such operations are necessary to correctly label the boxes?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

What will you call your mother's brother's brother-in-law?