Can you name some countries which do not have the alphabet 'A' in them?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

By moving exactly three matchsticks can you make the below equation true.It can be solved by 3 ways.

John and Jacob are twin brothers. One of them is a liar whereas the other one is a truth-teller.

I called their home number and one of them picked up.
I asked. 'Does John lie?' The person replied with a yes.

Whom did I talk with, John or Jacob?

Can you count the number of lines in the below picture?

How many times in a given day, minutes and hour clock comes in a straight line ?

There was a man he lives in a hotel each morning he presses the first floor button each evening if there is a person in the elevator he asks him to press the 10 floor button if there is no one in the elevator he takes the stairs why.

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

If 1+9+8=1, what is 2+8+9?

Two guards were guarding the camp.Guard-1 was looking towards the south to make sure no threat is coming from the road.Guard-2 was looking at the north to make sure no threat is coming from the top. Suddenly Guard-1 ask the Guard-2 why he is smiling?How Guard-1 knows that Guard-2 is smiling?