How can you write nineteen in a manner that if we take out one, it becomes twenty?

A dying old man wants to divide his entire land between his only two sons. Since his only wish is to treat them as equal as both of them have been too good to him, he wants to divide his land equally between them. The problem is that the land is significantly irregular in shape and thus there is no choice of cutting them into two equal halves.

Can you help him divide the land in a manner that both of his sons will be happy?

What Adam and Eve do not have but the rest of the people have?

I have some blue and red sock in my drawer. I have a total of 4 socks. I pick 2 socks and the chance that I get a pair of red socks is 1/2.

What is the chance of picking a pair of blue socks?

Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

What number comes next in this sequence:
7 8 5 5 3 4 4 _

Speaking of rivers, a man calls his dog from the opposite side of the river. The dog crosses the river without getting wet, and without using a bridge or boat. How?

By including only four matchsticks in below picture, you have to make "Four Triangles And Two Squares"

There are 3 apples in the basket and you take away 2. How many apples do you have now?