What number should come in place of the question mark below?

A famous swimmer can swim downstream in a lake in exactly 40 minutes with the lake current.
He can swim upstream in that lake in exactly 60 minutes against the lake current.
The length of the lake is 2 km.

How long he can cover the distance of one side at a still lake with no current?

The picture shows the dice results in each couple of throws. If they are actually following a pattern, can you find out the missing one?

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?

John was gifted a new Hayabusa. He drove x miles at 55mph. Then he drove x+20 miles at 40mps. He drove his bike for 100 minutes. How much distance did he travel?

Why is it very easy to weigh a fish?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Where do fish keep their money?

Can you place six matchsticks in a manner that each of the matchsticks is in touch with the other five matchsticks?