What is greater than gold but cannot be bought. it can never be sold and can earn if its sought. though it can be broken, it can still be fixed. for by birth it can't start nor by death it is ended.what am i?

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

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

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

A man dies of old age on his 25 birthday. How is this possible?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

There’s a one-story house in which everything is yellow. Yellow walls, yellow doors, yellow furniture. What colour are the stairs?

Andrew’s doctor gives him three pills and tells him to take one every half hour. How much time will have passed by the time Andrew’s taken all three pills?