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?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

A man and a dog were going down the street. The man rode, yet walked. What was the dog’s name?

A word I know,
Six letters contain,
Subtract just one,
And twelve is what remains.

There are three boxes. One is labeled "APPLES" another is labeled "ORANGES". The last one is labeled "APPLES AND ORANGES". You know that each is labeled incorrectly. You may ask me to pick one fruit from one box which you choose.

How can you label the boxes correctly?

Name a key which is hardest to turn.

There are nine letters in the below-given diagram. You have to form a nine-letter word using these letters.

You have to put a letter on the following to make it a meaningful word. The only challenge is that you can't use 'E'.

S E Q U E N C _

Give it food and it will live; give it water and it will die.

The following question it puts forth you:

25 - 55 + (85 + 65) = ?

Then, you are told that even though you might think it's wrong, the correct answer is actually 5!

Whats your reaction to it? How can this be true?