Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

Name a key which is hardest to turn.

You need to move three matchsticks to form three squares. Can you do it?

Can you find out which triangle will have a bigger area among the following?
1. A triangle with sides 300, 400 and 500
2. A triangle with sides 300, 400 and 700

While preparing the table for dinner, wife came up with an idea to tease his mathematician husband. She asked her husband to pick nine toothpicks and make ten without breaking any toothpick.

The husband was also smart and did it within seconds. How ?

There is a rock group of four men that do not sing. Name It?

Alpha is Beta's sister.

Gamma is a Beta mother.

Delta is Gamma's father.

Tango is Delta's mother.

Then,

How is Alpha related to Delta?

Can you quickly find which two matchstick figures are identical?

On rolling two dices (six-sided normal dice) together, what is the probability that the first one comes up with a 2 and the second one comes up with a 5?