Two guards were on duty outside a barracks. One faced up the road to watch for anyone approaching from the North. The other looked down the road to see if anyone approached from the South. Suddenly one of them said to the other, "Why are you smiling?"

How did he know his companion was smiling?

I am eight letters long - "12345678"
My 1234 is an atmospheric condition.
My 34567 supports a plant.
My 4567 is too appropriate.
My 45 is a friendly thank-you.
My 678 is a man's name.

What word am I?

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

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

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

Can you solve the photo plexer logic ?

Can you solve the tricky chess rebus puzzle below by ciphering the hidden meaning?

Below, you will find the mathematical proof that 10 equals 9.99999?. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10

What can go through glass without breaking it?

First, think of the colour of clouds. Next think the colour of snow. Last, think of the colour of the moon. Now, what do cows drink?