How many times in a given day, minutes and hour clock comes in a straight line ?

It spends most of its day eating white, but when it’s quick enough, it gets to eat fruit and sometimes some blue things. It’s in a dark room, where the walls are blue, it runs from a ghost that roams the halls and haunts it all the time. What is it?

What happened when the wheel was invented?

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.

I am an odd number. Take away a letter and I become even. What number am I?

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

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

I am a three digit number.
My tens digit is five more than my ones digit.
My hundreds digit is eight less than my tens digit.
What number am I?

It's pretty hard to give up.
If you remove a part of it, you will be left with a bit.
Even if you remove another part, the bit still remains.
Remove one more and it still remains.

What is it?