How to determine which combination of orders would be optimal, in Excel?

I am struggling with a small task in Excel. I have two options to choose from when ordering in bulk. Option A - 5 pieces for 80$. Option B - 30 pieces for 200$. I cannot buy single pieces and I have to buy in bulk. How can I write a formula that can check which combination of the bulk orders I should make? For example, if I want to order 34 pieces, then it would be better to order Option B once and Option A once, instead of ordering Option B twice or Option A 7 times.

I tried to find an equation, where the x-intercept would show how many Option A's to order but it only works in very simplistic cases and not for all possible inputs. I think that the answer to this might lie in an IF formula but I am not sure.