Below, you will find the mathematical proof that 10 equals 9.99999?. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10

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.

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

John was piloting a plane behind a car but was never able to overtake it. Why?

Which alphabet letter is a question?

What can jump higher than a building?

The product of three consecutive numbers is 7980.
Then the sum of these consecutive numbers would be?

Count the squares in the matchstick puzzle below?

Count the number of squares in the picture below.

Rearrange the letters in "new door" to make one word.