You are presented with three boxes. One of them has a red ball inside and the other two have a black ball inside each of them. You are asked to pick up the one with red ball and you pick one. Now, one of the other boxes is opened and it is found to have a black ball.

You are presented with a chance to change your box with the one that is left closed. Will you change your box? Why or why not?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

I hide my treasure in the ground, my tail is big and fluffy. If you spot me in a tree, please don’t call me scruffy. What am I?

John left on a horse on Thursday , was gone for two days, and came back on Thursday after completing his work. How did that happen?

how come the second man dies?

A girl is twice as old as her brother and half as old as her father. In 50 years, her brother will be half as old as his father. How old is the daughter now?

Buy me, smell me or deliver me, I do not change.

Who am I?

I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I?

John and his wife were living in a rural place. On a particular day, John's wife fell ill and he called the local doctor. When the doctor picked up, he said, "Doctor, my wife is ill. She might have appendicitis."

"This can't be possible! I took out her appendix two years ago myself," the doctor explained.

When diagnosed, John's wife was found to have appendicitis. How can this be possible?