What goes up but never comes down?

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.

What does this rebus riddle means ?

Can you complete the sequence puzzle?

AR TA GE CA LE VI LI _

I am quite hot but become too cold if you remove the first two letters. What am I?

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?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

One night, a woman receives a call from the police. They tell her that her husband was murdered and that she should come to the crime scene as soon as possible. The woman drops the phone, shocked, and drives 20 minutes to the crime scene. As soon as she reaches the crime scene, the police arrest her and she is convicted of murder. How do the police know she committed the crime?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

What is harder to catch the faster you run?