What four weights can be used to balance from 1 to 30 pounds?

Prove that twice of ten is the same as twice of eleven.

If we add four times the age of John four years from now to five times his age five years from now we get ten times his current age.

How old will John be two years from now?

There is an exact a week gap between Christmas and New Year. Hence, It is obvious that the new year that comes right after Christmas comes on the same day of the week.

A Strange thing happened in the Year 1777. Christmas occurs on Wednesday and New Year on Monday. How is that possible?

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?

The more it dries, the wetter it becomes. Can you tell what it is?

What you cannot hold but it is yours?

You can see three almost identical images below. Can you spot the odd one out from them?

What has a ring but no finger?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?