You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

Can you circle exactly four of these numbers such that the total is twelve?

1 6 1
6 1 6
1 6 1
6 1 6

What type of tree can I carry in my hand?

Replace each alphabet with the number (1-9) to make the below equation correct.

AB * C = DE - F = GH / I

When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

Spot 5 differences in two Christmas tree below:

If 21x = 79x, what is the value of x?

Why do people go to bed?

If "P" means "-", "Q" means "/", "R" means "+", and "S" means "*" then find the value of the following:

21 Q 7 R 9 S 10 P 13

Find the next number in the series

12, 20, 40, 72, 116, 172 ?