I am absolutely dogshit at using this software but know many of you are kings of understanding so hoping you can help me out.....

I have a coloumn of numbers derived from a simple equation (A)

A B C

345
560
1200
1650

What I want is a way for B to automatically be populated from the numbers in A in a specific way:
Any number from <500 then B equals exactly 500
Any number between 500-1000 then B rounds up to exactly 1000
Any number between 1000 and 1500 then B rounds up to 1500
And so on in increments of 500.

Coloumn C would need to be an equal column so that 500 from B would equally 50 in C or 1000 in B would equal 100 in C or 1500 in B would equal 250 in C

Can this be done??
I have no idea even how to google what I'm asking

I'm at work with limited mobile reception so apologies for not checking thread for replies but thanks in advance for any advice. Will be back online around 4.