How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

If an earthquake is 1 point higher on the Richter Scale than another earthquake which is actually 10 times stronger, how much stronger would an earthquake be if it was just half a point higher on the Richter scale?

Name a key which is hardest to turn.

Eight Chelsea player makes the following statements :

1. Seven of us are lying here.
2. Six of us are lying here.
3. Five of us are lying here.
4. Five of us are lying here.
5. Four of us are lying here.
6. Three of us are lying here.
7. My name is Torres.
8. My name is Lampard.

The last two are Lampard and Torres or maybe Torres and Lampard.
So can you deduce which of the last two is Lampard or Torres?

What is black when you buy it, red when you use it, and gray when you throw it away?

In the attached figure, you can see a chessboard and two rooks placed on the chess board. What you have to find is the number of squares that do not contain the rooks. How many are there?

A girl says this to her best friend: “I was born in 1955, and I celebrated my 17th birthday last weekend.” Her best friend thinks she’s lying, but she’s actually correct. How is that possible?

Can you make numbers like 24, using numbers 3,3,7 & 7 with any arithmetic operator?

Can you find out who is the kidnapper in below Picture and why, Explain ?

Spelt forwards I’m what you do every day, spelled backwards I’m something you hate. What am I?