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?

What type of curtain does this rebus mean

Can you count the number of triangles in the picture below?

I noticed one of the words in the oxford dictionary is spelled incorrectly. What about you?

You can hear me, but you can't touch or see me.

What am I?

If you toss a coin 10 times and it lands heads up every time, what are the chances it will land heads up if you toss it again?

By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?

I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

There is a square piece of paper with a hole that is denoted by the circle on the top right side in the given picture. You have to cut the paper in a manner that it forms two and only two separate pieces of paper and then rearrange the pieces in a manner that the holes come in the centre of the paper.

A large container is kept in open under the rain. Every passing hour, the water collected inside the container becomes double what it was.

In ten hours, the container is filled completely. Can you calculate how long would it have taken to be filled in half?