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?

A man is looking at a photograph of someone. His friend asks who it is. The man replies, “Brothers and sisters, I have none. But that man’s father is my father’s son.” Who was in the photograph?

There is something which you can be arrested for attempting but not for successfully completing.

Tell me the Hindi name of a Vegetable which if we remove 1st word will become a precious Stone and by removing the last word it will become a sweet eatable.

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?

What came first, the chicken or the egg?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

How much will a 38° angle measure when looked at under a microscope that magnifies ten times?

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

The ages of a father and son add up to 66.
The father's age is the son's age reversed.
How old could they be?
(3 possible solutions).