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.

The centre of the third figure is empty. What digit should fit inside?

Twice ten are six of us,

Six are but three of us,

Nine are but four of us;

What can we possibly be?

Would you know more of us?

Twelve are but six of us,

Five are but four, do you see?

What are we?

I look flat, but I am deep. Hidden realms I shelter. Lives I take, but the food I offer. At times I am beautiful. I can be calm, angry, and turbulent. I have no heart but offer pleasure as well as death. No man can own me, yet I encompass what all men must have. What am I?

What is 3/7 chicken, 2/3 cat and 2/4 goat?

A plane crashed between the border of Mexico and America. Where do you bury the survivors?

Solve the counting riddle by identifying the number of triangles in the given picture.

It is Secret Agent Bond Girl Friend's birthday but he is on a secret mission

Mr Bond has a secret device by which he can only use the below words for sending the message.

Dumbo, Nazi, Carrot, Ronda, Zambia, Racing, TinTin, Seou, Zareeba, Laltain, Saphire, Tar, Orphan, Audition, Biscotti.

Mr Bond sends the following message to her girlfriend:
Carrot Dumbo Nazi Racing Ronda Zambia TinTin Seou Laltain Zareeba Tar Biscotti Orphan Audition Snake

What does Mr. Bond's Message say?

When is the top of a mountain similar to a savings account?

What's the next in the series?

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?