Ok, I need a push in right direction on this

So, I have this pricelist that I am trying to make a spreadsheet for. I sell roofing and siding. Now the price on a 10x10 area which we call a square is floating. In other words if you buy a smaller roof the price per square will be higher. Here is real example

# of squares total price price per square

1 559.80 559.80
2 724.56 362
3 925.33 308.44
4 1108.10 277.02

Let's skip a few rows and we will see that the step becomes considerably smaller when we move into big roofs.

23 4580.70 199.10
24 4763.47 198.40


My question, hence will be twofold.

1. Can I figure some kind of formula (function or whatever - I am not dumb but not a mathematician either) or am I stuck forever figuring each value?

2. How can I make Excel calculate this for me based on some kind of math formula.


Thank you everybody who are smarter and more experienced than I am, help me not to get fired.


Alex