In the city of Brain Teasers, 5% of people do not list their phone numbers. Now if we select random 100 people from the phone directory, then how many people selected will have unlisted phone numbers?

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

If,

20 % 5 = 24

21 % 7 = 33

42 % 6 = 67

Then;

66 % 6 = ?

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?

There is an English word that can be used up to four times in a row without modifying the spelling and form a valid grammatical sentence.

Do you know what word is that?

From a pack of 52 cards, I placed 4 cards on the table.

I will give you 4 clues about the cards:

Clue 1: Card on left cannot be greater than the card on the right.
Clue 2: Difference between the 1st card and 3rd card is 8.
Clue 3: There is no card of an ace.
Clue 4: There are no face cards (queen, king, jacks).
Clue 5: Difference between the 2nd card and 4th card is 7.

Identify four cards?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

I taste better than I can smell. Who am I?

Three ants are sitting at the three corners of an equilateral triangle. Each ant starts randomly picks a direction and starts to move along the edge of the triangle. What is the probability that none of the ants collide?

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?