A man desired to get into his work building, however he had forgotten his code.
However, he did recollect five pieces of information
* Fifth number + Third number = 14
* The fourth number is one more than the second number.
* The first number is one less than twice the second number.
* The second number and the third number equals 10.
* The sum of all five numbers is 30.

What is the code ?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

Find the last number in the series below:

voN luJ yaM raM ---

Analyze and find the missing item in the sequence:
16, 06, 68, 88, __, 98

If 21x = 79x, what is the value of x?

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

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?

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

You have two buckets - one holds exactly 5 gallons and the other 3 gallons. How can you measure 4 gallons of water into the 5 gallon bucket?

(Assume you have an unlimited supply of water and that there are no measurement markings of any kind on the buckets.)

Look at the picture and find out which square is not linked with any of the other squares.