"Did you think to buy a dozen eggs?"
Translation:Tu as pensé à acheter une douzaine d'œufs ?
You have to forget this reasoning quickly, otherwise you'll make a lot of mistakes. I translate the sentence into two steps:
- Did you think to (think about)... Tu as pensé à/Vous avez pensé à
- buy a dozen eggs... acheter une douzaine d'oefs.
The first step (penser à quelque chose) is essential for a better understanding (quelque chose = buying a dozen eggs). Good luck!
https://www.lawlessfrench.com/vocabulary/approximate-numbers/ has a very good explanation. But I think in this situation since the item discussed is eggs (which commonly come in dozens or half-dozens) it probably means exactly twelve. In Canadian English when we say dozen, we mean exactly twelve.