What is both possible and impossible at the same time?

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?

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?

In a school, there are four subjects. Seventy percent of students study English, seventy five percent of students study Science, eighty five percent of students study Mathematics and eighty percent of students study Spanish.

Can you calculate the percentage of students that study all four subjects?

Find the 8 in the below-given Image.

The more it dries, the wetter it becomes. Can you tell what it is?

Can you find out which options fits best with the missing column?

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?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

Double it and multiply it by 4. Then divide it by 8 and you’ll have it once more. What number is it?