# Principal in the School

A high school has a strange principal. On the first day, he has his students perform an odd opening day ceremony:

There are one thousand lockers and one thousand students in the school. The principal asks the first student to go to every locker and open it. Then he has the second student go to every second locker and close it. The third goes to every third locker and, if it is closed, he opens it, and if it is open, he closes it. The fourth student does this to every fourth locker, and so on. After the process is completed with the thousandth student, how many lockers are open?

# Similar Riddles

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

Asked by Neha on 14 May 2021

##### Relationship Riddle

That attorney is my brother, testified the accountant.

But the attorney testified he didn't have a brother.

Who is lying?

Asked by Neha on 14 Dec 2020
##### Enemy Challenge

our enemy challenges you to play Russian Roulette with a 6-cylinder pistol (meaning it has room for 6 bullets). He puts 2 bullets into the gun in consecutive slots, and leaves the next four slots blank. He spins the barrel and hands you the gun. You point the gun at yourself and pull the trigger. It doesn't go off. Your enemy tells you that you need to pull the trigger one more time, and that you can choose to either spin the barrel at random, or not, before pulling the trigger again. Spinning the barrel will position the barrel in a random position.

Assuming you'd like to live, should you spin the barrel or not before pulling the trigger again?

Asked by Neha on 04 May 2022

##### Apple on the boat riddle

A few friends are enjoying their sea voyage in a boat full of apples. On the way, they felt hungry and thus decided to eat the apples. Together, they ate two dozen of apples. When they have eaten the apples, will there be any change in the water level?

Asked by Neha on 06 May 2021
##### Magic Number

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

Asked by Neha on 04 Oct 2021
##### Always in you

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

Asked by Neha on 09 Apr 2022

##### Magic Math

A 3 digit number is such that it's unit digit is equal to the product of the other two digits which are prime. Also, the difference between it's reverse and itself is 396.

What is the sum of the three digits?

Asked by Neha on 13 Dec 2020
##### Twenty One Eyes can not see

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see?

Asked by Neha on 14 Sep 2021

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

Asked by Neha on 14 May 2021

##### Dies when his Suit Torn

A man was just doing his job when his suit was torn. Why did he die three minutes later?

Asked by Neha on 15 Sep 2021

### Amazing Facts

###### Challenging

There is a cryptic organization called Cicada 3301 that posts challenging puzzles online, possibly to recruit codebreakers and linguists.