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

You find yourself in a strange place guarded by two guards.One of the guard always say truth while other always lies.You don't know the identity of the two.You can ask only one question to go out from there. What should you ask?

How many words can a pen with half refill write?

What Time Should the last watch show in the below figure?

What number comes next in this sequence:
7 8 5 5 3 4 4 _

15 caves are arranged in a circle at the temple of doom. One of these caves has the treasure of gems and wealth. Each day the treasure keepers can move the treasure to an adjacent cave or can keep it in the same cave. Every day two treasure seekers visit the place and have enough time to enter any two caves of their choice.

How do the treasure seekers ensure that they find the treasure in the minimum number of possible days?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

How many triangles can you find in this given picture?

what does this picture(rebus) riddle means ?

You have an empty wine bottle with a cork that has been secured at the top in a normal way. There is a metal ring inside the bottle that is suspended by a string.

How can you make the metal ring drop to the bottom if you are not allowed to touch anything - not the bottle, not the cork, not the thread and not the ring?