Questions & Answers about نسبت قرمز به آبی اینجا دو به یک است.
How do we express the 'two to one' proportion in this sentence?
We use the simple structure [Numeral] + be + [Numeral]. So 'two to one' is do be yek. The preposition be (to) functions exactly as it does in English when talking about ratios and proportions.
Why is there an ezafe connecting nesbat and qermez, but not before be?
The word nesbat (ratio) is a noun that belongs to or describes qermez (red), so it takes the ezafe linking vowel to become nesbat-e qermez. However, be is a preposition. We drop the ezafe before prepositions, which is why it is just qermez be aabi without an extra connector.
Could injaa (here) be placed somewhere else in this sentence?
Yes. While placing it right after the subject phrase and before the numbers (...aabi injaa do...) is very natural, Farsi adverbs of place are flexible. You could easily put it at the very beginning of the sentence (injaa nesbat-e...) without changing the meaning.
Does the word nesbat only refer to mathematical ratios?
It is used for mathematical proportions like in this sentence, but it is also the everyday word for 'relation' or 'connection'. For example, if you want to ask how two people are related to each other, you would also use nesbat.