The host of a game show offers the guest a choice of three doors. Behind one is an expensive car, but behind the other two are goats.
After you have chosen one door, he reveals one of the other two doors behind which is a goat (he wouldn't reveal a car).

Now he gives you the chance to switch to the other unrevealed door or stay at your initial choice. You will then get what is behind that door.

You cannot hear the goats from behind the doors, or in any way know which door has the prize.

Should you stay, or switch, or doesn't it matter?

How many triangles are there in the picture below?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Find the last number in the series below:

voN luJ yaM raM ---

I get hot but I never sweat,
I cook food but I am not a chef,
I have a door but you can't enter me,
I have a light but I am not a lamp.
Who am I?

2, 3, 5, 9, 17, _ What is the next number in the sequence?

Most people think of me as money. But when they find me in the water, they won’t get any money out of me. What am I?

Name a key which is hardest to turn.

A sundial has the fewest moving parts of any timepiece. Which has the most?

My thunder comes before the lightning; my lightning comes before clouds; my rain dries all the land it touches. What am I?