A new Engineering building containing 100 offices had just been completed. John was hired to paint the numbers 1 to 100 on the doors. How many times will John have to paint the number nine (9)?

Replace the question mark with the correct number.

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

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different.

How do you measure 45 minutes?

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.

Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.

"Are you twins," ask the headmaster.
"No," replies the boys.

Is it possible?

Living above a star, I do not burn
Eleven friends and they do not turn
I can just be visited in a sequence, not once or repeatedly
PQRS are my initials
Can you tell my name accurately?

Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?

Replace the question mark with the number below given a simple math problem.

What is the longest word in the dictionary?