why number 8549176320 is one of a kind?

John and Jenni are a married couple. They have two kids, one of them is a girl. Assume safely that the probability of each gender is 1/2.
What is the probability that the other kid is also a girl?

Hint: It is not 1/2 as you would first think.

Intelligence Agency need to break the vault but the problem is that they are not able to break the vault.

On the vault, a text is written as:

31 11 33 33 43 45
21 25
31 24 11 31 51 41

To Break the code Intelligence Agency brings a mathematician named Joseph.
Minutes later he deciphers the code.

Whats the code?

There are 2 sand hourglasses.

The small one can measure 5 hours and the large one can measure 7 hours.

How can we measure 16 hours with 2 sand hourglasses running together ?

Why is the Hole below a Lock?

A man in a car saw a Golden Door, Silver Door and a Bronze Door. What door did he open first?

I am white when I am dirty, and black when I am clean. What am I?

Can you find the odd number in the following?

2716, 4135, 5321 and 7145

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

I am a white box having no key or lid.
Yet there is a golden treasure inside it.

What Am I?