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

When is the top of a mountain similar to a savings account?

Asked by Neha on 18 Aug 2025


Only one color, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

Asked by Neha on 14 May 2021

Can you identify the direction in which this bus is moving; left or right?

Hint: The bus is moving on the roads of London.


Find Bus Direction

Asked by Neha on 17 May 2021


John was drowned by he was not wet. How?

Asked by Neha on 16 May 2025

Christina is practising her dance steps along with her friends. In a particular sequence, all of them form a row. At that point, Niharika is standing in the 4th position from either end of the row.
Can you find out how many girls are practising together?

Asked by Neha on 10 Oct 2024

There is a shop where written:
Buy 1 for $1
10 for $2
100 for $3
I needed 999 and still only paid $3. How could this be financially viable for the shop-keeper?

Asked by Neha on 24 Dec 2025


John gave half of the apples he had plus one more to Jacob. He gave half of the remaining ones plus one more to James. Now, John was left with just one apple.

Can you find out how many did he have in the beginning?

Asked by Neha on 13 Nov 2024

How can you tell a raw egg from a hard-boiled egg?

Asked by Neha on 09 Jan 2025

Without looking at a calendar, within a minute name, a boy's name using 5 consecutive 1st letters of 5 consecutive months

Asked by Neha on 22 Apr 2025


A sea diver is a real show-off. He showed everyone that he can hold his breath underwater for 15 minutes.

I went to the diver and told him that I can be underwater for double the time i.e 30 minutes.
He responded that he will give me 100$ if I would be able to do it. I won 100$.

What did I do?

Asked by Neha on 06 Mar 2025

Hot Articles

Amazing Facts

Challenging

There is a cryptic organization called Cicada 3301 that posts challenging puzzles online, possibly to recruit codebreakers and linguists.