How many pages of the Aeneid did Virgil write per day?

Approximately three lines per day

There is a tradition that Virgil worked at about a rate of 3 lines per day. Since the poem is 9896 lines long, and we know that Virgil worked on it for the last ten years of his life, this approximation seems about right. The number of pages depends upon how many lines are printed on a page. If there are 30 lines per page, the answer is about a tenth of a page per day, or 10 days per page.

This is of course an average; one would expect that he wrote more on some days and none on others. It seems probable that the tradition of three lines per day was arrived at by just this calculation.