Learn Farsi: من حدود سه وعده را به پنج وعده ترجیح می‌دهم. - I prefer about three meals to five meals.

We use the compound verb tarjih dâdan. The thing you prefer (X) acts as the direct object, marked here by râ. The thing you prefer it over (Y) takes the preposition be (to). So the syntactic frame is [X] râ be [Y] tarjih midaham.

Why does the direct object marker râ come exactly where it does?

The phrase hodud-e se va'de (about three meals) is a specific direct object, so the entire noun phrase gets the râ marker. In Farsi syntax, the specific direct object plus râ naturally comes before prepositional phrases like be panj va'de.

Is there a hidden ezafe linking hodud to the rest of the phrase?

Yes! It is pronounced hodud-e se va'de. The word hodud literally means boundaries, but when linked with an ezafe to a number, it translates to about or approximately.

Could I use ghazâ instead of va'de for meal here?

Not quite. While ghazâ means food or the physical meal on your plate, va'de refers to a scheduled serving or the time slots for eating. When counting how many times a day you eat, you use va'de.