In a box, there is a jumble of 7 red balls, 6 blue balls, 5 green balls, and 4 yellow balls. What is the minimum number of balls, will you have to pick up so that you have at least 4 balls of the same colour?

A dying old man wants to divide his entire land between his only two sons. Since his only wish is to treat them as equal as both of them have been too good to him, he wants to divide his land equally between them. The problem is that the land is significantly irregular in shape and thus there is no choice of cutting them into two equal halves.

Can you help him divide the land in a manner that both of his sons will be happy?

You are stuck on an island where you have nothing. You find four pieces of paper somewhere on the island. What will be your strategy to escape from the island safely?

PS: No other resource is available to you on the island, neither can you build anything.

The measurement of time, That can't be found on a clock, But can be looked upon on a map.

Who is He ?

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?

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

What has many teeth, but cannot bite?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

Give it food and it will live; give it water and it will die.

The following sentence is false. The preceding sentence is true.
Are these two sentences true or false?