Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

It spends most of its day eating white, but when it’s quick enough, it gets to eat fruit and sometimes some blue things. It’s in a dark room, where the walls are blue, it runs from a ghost that roams the halls and haunts it all the time. What is it?

What kind of band never plays music?

Living above a star, I do not burn
Eleven friends and they do not turn
I can just be visited in a sequence, not once or repeatedly
PQRS are my initials
Can you tell my name accurately?

Name a key which is hardest to turn.

When is the top of a mountain similar to a savings account?

Akbar called Birbal and asked him to draw a line on the floor. He asked Birbal to make that line smaller without erasing it. Birbal smiled and did it before Akbar could blink his eyes.

How did he managed to do it?

Why did Navjot Singh Sidhu put the new January calendar in the freezer

My location can be determined by the below rebus.
So where am i ?

What brings you down but never up?