If,

20 % 5 = 24

21 % 7 = 33

42 % 6 = 67

Then;

66 % 6 = ?

Why do we preferably have round manhole covers and not square ones?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

Krish is 45 years old and his mother Crishtina is 73 years old.

Can you find out how many years ago, his mother was three times his age?

What time is it when an elephant sits on a fence?

In the given figure, move three matchsticks so that the resulting figure contains two rectangles.

Give it food and it will live; give it water and it will die.

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

Your job is to measure 45 minutes if you have only two cords and matches to light the cords.

1. The two cords are twisted from various materials, so their different segments can burn at different rates.
2. Each cord burns from end to end in exactly one hour.

Describe your way of measuring the 45 minutes.

What can run but never walk, have a mouth that never speaks, have a head that never weeps, and have a bed but never sleeps?