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?

I am a type of word that is spelt incorrectly or used differently, on purpose for humour. What am I?
Hint 1: You can find me in a joke.
Hint 2: I am a play on words.

What is the last thing you take off before bed?

An exterior architect is asked by a builder to plant seven trees in a manner that there are exactly six rows of trees in a straight line and each row has three trees in particular.

How will he do it?

Why 1729 is a magic number? Answer Logically.

What number divided by 4 is the same as that number minus 4?

Jim has three close friends at his school: Michael, John and Alice. Two of them play football, two play basketball and two play hockey. The friend who does not play hockey does not play basketball as well. The friend who does not play football does not play hockey.

Can you identify which sport/s is played by which person?

Count the number of triangles in the picture below:

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

They do not possess flesh or feathers or scales or bone
But still, they are blessed with fingers and thumbs of their own.