John buys rice at Rs.60/kg from Britain and then sells them at Rs.5/kg in India. As a result of this, he becomes a millionaire. How come?

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?

It belongs to you, but other people use it more than you do. What is it?

A man stands on one side of a river, his dog on the other. The man calls his dog, who immediately crosses the river without getting wet and without using a bridge or a boat. How did the dog do it?

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

There is a circular car race track of 10km. There are two cars, Car A and Car B. And they are at the exact opposite end to each other. At Time T(0), Both cars move toward each other at a constant speed of 100 m/seconds. As we know both cars are at the same speed they will always be the exact opposite to each other.
Note, at the center, there is a bug which starts flying towards Car A at time T(0). When the bug reaches car B, it turns back and starts moving towards the car A. The speed of bug is 1m/second. After 5 hours all three stop moving.
What is the total distance covered by the bug?

A sundial has the fewest moving parts of any timepiece. Which has the most?

I am the beginning of everything, the end of everywhere. I'm the beginning of eternity, the end of time and space. What am I?

What happened when the wheel was invented?

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?