Find The Next Number in the series:

12 13 15 17 111 113 117 119 123 ?

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.

Which tank will fill first?

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

What is the unique property of the following words ?
* Revive
* Banana
* Grammar
* Voodoo
* Assess
* Potato
* Dresser
* Uneven

What animal walks on four legs in the morning, two legs during the day, and three legs in the evening?

Oedipus, the king of Thebes, figured out the answer to the riddle:

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

What makes this number unique: 8,549,176,320?

Why is it very easy to weigh a fish?