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.

This puzzle is for Harry Potter fans. Do you know why Tom Riddle is called Lord Voldemort?

Can you name an animal whose killing cannot be performed without spilling your own blood?

What do you answer even though it never asks you questions?

The day after tomorrow will be three days before Tuesday. Can you find out what is today?

A car meter reading shows 72927 miles a palindromic number.
what is the minimum number of miles you would need to travel to see another palindromic number on the car meter reading?

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

Every words stands for unique digit that makes the arithmetic equation true

SEVEN + SEVEN + SIX = TWENTY.

What are the digits ?

What is common among 11, 69, and 88?

Replace the question mark with the correct number.

2 + 2= 4
3 + 3= 18
4 + 4= 48
5 + 5= ?