A Doctor always sneezes before the rain. Doctor sneezes, Will it rain?

Do you know of a place where the wind blows south and then suddenly shifts direction towards the north?

Remove two matchsticks to make the below equation correct.

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

A father's child, a mother's child, yet no one's son.

Who am I?

In the picture that is attached with this question, you can find a square which comprises of four little squares inside it. Consider this square to be made with matchsticks. You have to remove two matchsticks such that only two squares remain instead of five.How will you do it ?

We have shown you a regular water barrel as below. Without using any measuring device can you check if the barrel is more than half-filled or less than half-filled?

Decode below rebus
D
N
A
T
S , D

Assume there are approximately 5,000,000,000 (5 billion) people on Earth. What would you estimate to be the result, if you multiply together the number of fingers on every person's left hand? (For the purposes of this exercise, thumbs count as fingers, for five fingers per hand.) If you cannot estimate the number then try to guess how long the number would be.