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?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

In Greek mythology, the Sphinx sat outside of Thebes and asked this riddle of all travellers who passed by. If the traveller failed to solve the riddle, then the Sphinx killed him/her. And if the traveller answered the riddle correctly, then the Sphinx would destroy herself. The riddle:

What goes on four legs in the morning, on two legs at noon, and on three legs in the evening?

Oedipus solved the riddle, and the Sphinx destroyed herself.

I noticed one of the words in the oxford dictionary is spelled incorrectly. What about you?

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

Using Only Five 5's and any mathematical operator make sum as 37

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

I am white when I am dirty, and black when I am clean. What am I?

What word is identified by the below rebus?

Your Your Your Your Your
Your Your Your Your Your