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

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

John is the son of Jacob.
So,
Jacob is the_____of John's father?

Can you find out the remainder when 3^300 is divided by 5?

How many points are there on the globe where, by walking one mile south, then one mile east and then one mile north, you would reach the place where you started?

As we know that white starts the game of chess. Can you find the scenario shown in the picture below is possible when all the white pieces are at the original place while the black pawn is not as in the below picture?

What is so fragile that saying its name breaks it?

What will you call your mother's brother's brother-in-law?

A Club organizes a Running Race, and John, Jacob, Minda, and Tony participated.

The results are as follows

John beats Jacob
Minda beats Toni
Toni beats John

Who came first in the race?

I inserted a coin in a bottle and closed its mouth with the help of a cork. Now, I was able to take the coin out from the bottle without taking out the cork or breaking the bottle. Can you tell me how I did it?