John is the son of Jacob.
So,
Jacob is the_____of John's father?

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

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).

I am thinking of a five-digit number such that:
The first and last digits are the same, their submission is an even number and multiplication is an odd number and is equal to the fourth number. Subtract five from it and we obtain the second number. Then divide into exact halves and we get the 3rd number.

What number I am thinking of?

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?

What can run but never walk, have a mouth that never speaks, have a head that never weeps, and have a bed but never sleeps?

You see me once in June, twice in November, and not at all in May. What am I?

A sundial has the fewest moving parts of any timepiece. Which has the most?

What is the Surname of Barbie Doll?

Can you name some countries which do not have the alphabet 'A' in them?