There was an aeroplane crash, every single person died, but two people survived. How is this possible?

Use the digits from 1 up to 9 and make 100.

Follow the rules.
=> Each digit should be used only once.
=> You can only use addition.
=> For making a number, two single digits can be combined (for example, 4 and 2 can be combined to form 42 or 24)
=> A fraction can also be made by combining the two single digits (for example, 4 and 2 can be combined to form 4/2 or 2/4)

Question: how can we do this?

You walk into a room and see a bed. On the bed, there are two dogs, five cats, a giraffe, six cows, and a goose. There are also three doves flying above the bed. How many legs are on the floor?

Can you count the number of triangles in the picture below?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

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

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

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.

Why do Chinese men eat more rice than Japanese men do ?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?