I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

You have a 12 liters jug full of water. You have two empty 8 liters and 5 liters jug. How can you divide the water into two equal parts using these jugs?

You are in a room with no metal objects except for two iron rods. Only one of them is a magnet.
How can you identify which one is a magnet?

What number divided by 4 is the same as that number minus 4?

How many triangles can you find in this given picture?

In the given figure, you can see that four match sticks are used to form a square. Can you form five squares by using six matches?

Its something that each of us devours,
Not just us but birds, beats, trees, and flowers,
Frets iron and nibbles steel,
Toil hard stones to meal,
Exterminates king, collapse town,
And blows the mountains down.

What two things can you never eat for breakfast?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

John drives to his office at 20km/hr. After reaching the office, he realizes that today is a holiday. He went back at an average speed of 30km/hr. Discounting the time spent in the stoppage what was the average speed of his journey?