It's a protector.
It sits on a bridge.
One individual can see directly through it, while others wonder what it hides.

What is it?

4 fathers, 2 grand-fathers and 4 sons went to watch the movie.What is the minimum number of tickets they need to buy ?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

There are 2 sand hourglasses.

The small one can measure 5 hours and the large one can measure 7 hours.

How can we measure 16 hours with 2 sand hourglasses running together ?

We have four gears with below features=> Both Gear A and D has 60 teeth=> Gear B has 40 teeth=> Gear C has 20 teeth=> Every two minutes, Gear B makes 25 full turns.What is the relative speed of Gear A and Gear B?

What is the riddle which can be asked all day with a different correct answer each time.

There are three boxes on a table. One of the box contains Gold and the other two are empty. A printed message contains in each box. One of the message is true and the other two are lies.

The first box says "The Gold is not here".

The Second box says "The Gold is not here".

The Third box says "The Gold is in the Second box".

Which box has the Gold?

You and your two friends are working in a multinational company. How can you three find out the average salary of you all without disclosing your own salary to the other two?

Can you find out the number of the parking space in which the car is parked?

Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?