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.

Make the seating arrangement of 10 children in such a way that there are 5 rows with 4 children in each row.

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

We know that the number 7 is the prime followed by a cube. Which next number is also a prime followed by a cube?

Count The number of F's in the paragraph below:

"FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS"

No one wants to have it, but if one got it, he does not want to lose it. What is It?

What breaks yet never falls, and what falls yet never breaks?

What's the only room from which no one can enter or leave

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

I always drive my customer away.

Who am I?