The more of this there is, the less you see. What is it?

If,

A = 1

B = 2

C = 3

...

...

Z = 26.

Based on above rule, you need to find an eleven letter word whose letter sum is equal to 52.

How can a man go eight days without sleep?

I am white when I am dirty, and black when I am clean. What am I?

By removing one matchstick and adding one matchstick, can you convert the word "ZOO" to an animal name?

A mother is 21 years older than her child. In exactly 6 years from now, the mother will be exactly 5 times as old as the child.
Where's the father?

A man is shown a portrait painting. He looks closely, then tells, “Brothers and sisters have I none, but that man’s father is my father’s son!” Who is the man in the portrait?

In a basket of apples,
when counted in twos, there was one extra
when counted in threes, there were two extra when counted in fours, there were three extra
when counted in fives, there were four extra
when counted in sixes, there was five extra.

However, if the apples were counted in sevens, no extra apple was left. Can you calculate the minimum number of apples that were present in the basket?

Chef Andrea has to light the kitchen stoves to open her restaurant for the day. There are three stoves in the kitchen: A glass stove, a brick stove, and a wood stove. She only has one match. Which does she light up first?

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?