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 have one of the three numbers: 1, 2, or 3 in my mind. I speak only truth. You can ask me just one question for which I will only reply in yes or no or don't know. What question will you ask from me so that you are able to know the number?

I am a five-letter word and people eat me. If you remove the first letter I become an energy form. If you remove the first two letters, I am needed to live. Scramble the last three letters and I am a drink. What word am I?

At my favorite fruit stand,
an orange costs 18,
a pineapple costs 27,
and a grape costs 15.
Using the same logic, can you tell how much a mango costs?

The dirtier I get, the whiter I look. Who am I?

What have one eye but still cannot see?

Identify the 10 differences between the two given pictures.

How could a baby fall out of a twenty-story building onto the ground and live?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

In the image below, can you find the value of an angle(y)