What is the longest word in the dictionary?

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

What does this rebus mean?

O
N
C
E
TIME

A girl is twice as old as her brother and half as old as her father. In 50 years, her brother will be half as old as his father. How old is the daughter now?

What does this simple rebus mean?

You can see three almost identical images below. Can you spot the odd one out from them?

Cristina was born in 1888. She just had her 30th birthday today how did that happen?

Find the next number in the series

12, 20, 40, 72, 116, 172 ?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

In the picture, you can see a chess board. On the top left position, the K marks a knight. Now, can you move the knight in a manner that after 63 moves, the knight has been placed at all the squares exactly once excluding the starting square?