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?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

how come the second man dies?

On her drawing table, Sayna lit 12 coloured candles. A few seconds later she blew two candles off.

How many candles Sayna have at the end?

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

If you toss a coin 10 times and it lands heads up every time, what are the chances it will land heads up if you toss it again?

No one wants to have it, but if one got it, he does not want to lose it. What is It?

What is at the end of a rainbow?

How high do you have to count before you use the letter “a” in the English spelling of the whole number?

What is always in front of you but can’t be seen?