In apex 4.2, for classic reports, how can I ensure to show 50 OR 75 rows per page. Given pagination schemes only allow showing 15 rows per page.
Use the Number of Rows report attribute. Note that pagination settings are cached for the duration of the session. For this change to be instantly visible, either log out, restart the brower, and log in again, or manually re-request the page from the browser address bar, adding 'RP' in the ClearCache position in the URL. Do not set anything in Number of Rows (Item) unless you intend to specify the number of rows using an item.