With the extra capacity black ink cart, I have printed 25,000 black and white typed pages using 52 ink carts. I think that's an average of 500 pages per cart.

Most were standard mode. They were mostly news stories. Some (but not most) pages were not totally full. For instance if the news story were 3 pages long, the last page was often (but not always) partial, such as 1/4 to 3/4 full. I went through 4 reams of paper and 4 ink carts pre month for 14 months.