Roundoff Riddle

Find a 9-digit number, which you will gradually round off starting with units, then tenth, hundred etc., until you get to the last numeral, which you do not round off. The rounding alternates (up, down, up ...). After rounding off 8 times, the final number is 500000000. The original number is commensurable by 6 and 7, all the numbers from 1 to 9 are used, and after rounding four times the sum of the not-rounded numerals equals 24.




Similar Riddles

Two girls were born to the same mother, on the same day, at the same time, in the same month and year and yet they're not twins. How can this be ?

Asked by Neha on 26 May 2021


I have two coins.
* One of the coins is a faulty coin having a tail on both sides of it.
* The other coin is a perfect coin (heads on side and tail on other).

I blindfold myself and pick a coin and put the coin on the table. The face of the coin towards the sky is the tail.

What is the probability that another side is also tail?

Asked by Neha on 07 Jun 2023

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

Asked by Neha on 17 May 2021


Imagine you are in a room with no windows or doors. How will you get out?

Asked by Neha on 25 Oct 2025

0 0 0 = 6
1 1 1 = 6
2 2 2 = 6
3 3 3 = 6
4 4 4 = 6
5 5 5 = 6
6 6 6 = 6
7 7 7 = 6
8 8 8 = 6
9 9 9 = 6

You can use any mathematical symbols in the space provided to make all above algebraic expressions true.

Asked by Neha on 24 Jul 2021

There were five men at church, and it started raining while they were outside. The four that ran still got wet, but the one that was still stayed completely dry. Why did he stay dry?

Asked by Neha on 19 Jun 2025


Which is the smallest number that you can write using all the vowels exactly once?

Asked by Neha on 11 May 2024

How much will a 38° angle measure when looked at under a microscope that magnifies ten times?

Asked by Neha on 17 May 2021

Why did the Girl throw the butter out of the window?

Asked by Neha on 19 Aug 2024


If a zookeeper had 100 pairs of animals in her zoo, and two pairs of babies are born for each one of the original animals, then (sadly) 23 animals don’t survive, how many animals do you have left in total?

Asked by Neha on 05 Aug 2025

Hot Articles

Amazing Facts

Out of the Box

The phrase “thinking outside the box” was popularised from the solution to a topographical puzzle involving 9 dots in a box shape.