10+10 and 11+11 can give you the same answer.

Explain how?

I am eight letters long - "12345678"
My 1234 is an atmospheric condition.
My 34567 supports a plant.
My 4567 is too appropriate.
My 45 is a friendly thank-you.
My 678 is a man's name.

What word am I?

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

Take away the whole and some still remain. What is it?

A doctor and a boy were fishing. The boy was the doctor’s son, but the doctor was not the boy’s father. Who was the doctor?

I have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?

How can a man go eight days without sleep?

Solve the rebus riddle in the picture below.

I live in a bowl. I can swim. I have a tail. I also have fins and big eyes. What am I?

What kind of storm is always in a rush?