Maths Logic

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




Similar Riddles

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.

Asked by Neha on 25 Aug 2023


In a fruit store, there was a unique weighing machine that was made to weigh only cherries and strawberries as they were priced the same.

Other fruits like watermelons or mango had different machines as they were expensive.

A man successfully buys watermelons at the price of cherries. How?

Asked by Neha on 30 Apr 2023

At a party, there are five people and a whole round cake lying at the centre of the table. Only four people will make a cut and take their piece and the last one will get the remaining piece on the table. How can they make sure that everyone gets a 1/5th of the piece?

Asked by Neha on 20 Sep 2024


Most people think of me as money. But when they find me in the water, they won’t get any money out of me. What am I?

Asked by Neha on 26 Oct 2025

There’s a girl who has a large family. She has an equal amount of brothers and sisters, but each brother only has half as many brothers and sisters. What’s the correct amount of brothers and sisters?

Asked by Neha on 05 Jun 2025

Which English verb becomes past tense just by rearranging the letters?

Asked by Neha on 07 Sep 2025


I am a word that begins with the letter “i.” If you add the letter “a” to me, I become a new word with a different meaning, but that sounds exactly the same. What word am I?

Asked by Neha on 19 Mar 2025

What can you catch but never throw?

Asked by Neha on 14 May 2021

Bay of Bengal is in which state?

Bay of Bengal

Asked by Neha on 12 Mar 2021


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

Count the Quadrilaterals

Asked by Neha on 14 Mar 2023

Hot Articles

Amazing Facts

Artificial Intelligence

Artificial Intelligence has crushed all human records in the puzzle game “2048,” achieving a high score of 839,732 and beating the game in only 973 moves without using any undo.