Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C

In four steps you need to move the word 'cold' From 'warm' by replacing one alphabet at a time such that every word formed at each step is acceptable in English Dictionary.

You are given 2 eggs.
You have access to a 100-storey building.
Eggs can be very hard or very fragile means it may break if dropped from the first floor or may not even break if dropped from 100th floor, Both eggs are identical.
You need to figure out the highest floor of a 100-storey building an egg can be dropped without breaking.
Now the question is how many drops you need to make. You are allowed to break 2 eggs in the process

Can you think of a smallest +ve number such that if we shuffle the digits of the number, the new number becomes double the original number?

A person is found murdered in his Chamber. When the crime scene is investigated, the Investigator find out that there is a calendar on which the victim has written a few numbers with his blood. The numbers are 4, 11, 11 and 4.

There are four suspects in the murder, John, Jacob, Anna and Lee. Can you find out who is the murderer?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

One is to three as three is to five and five is to four and four is the magic number.
What is the pattern?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see?

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?