Can you find out which number multiplied by itself will give the output as 12345678987654321?

Can you write down eight eights so that they add up to one thousand?

Can you find a number that lies one third of the distance between 1/3 and 2/3?

How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

We have arranged an array of numbers below. What you have to do is use any kind of mathematical symbol you know excluding any symbol that contains a number like cube root. You can use any amount of symbols but you have to come up with a valid equation for all of them.

0 0 0 = 6
1 1 1 = 6
2 + 2 + 2 = 6
3 3 3 = 6
4 4 4 = 6
5 5 5 = 6
6 6 6 = 6
7 7 7 = 6
8 8 8 = 6
9 9 9 = 6

I am a number I am not an odd number I am higher than 90 I am not higher than 100 If you subtract me from 100, you get nothing. What number am I?

We know that the number 7 is the prime followed by a cube. Which next number is also a prime followed by a cube?

Divide 110 into two parts so that one will be 150 per cent of the other. What are the 2 numbers?

Find three whole, positive numbers that have the same answer when multiplied together as when added together.