: Does PageRank flow to pages that are only listed in the sitemap.xml? Let's say you have a small website that has a PR of 3. On top of that you have on the domain itself a blog that is

@Pope3001725

Websites don't have PageRank, web pages have PageRank.
XML sitemaps do not affect PageRank in anyway.
If two websites are using the same domain name but do not link to each other they will not influence the PageRank of each other's pages. Domains have no influence PageRank.
PageRank is only influenced by incoming links, both internal and external. So any pages in that blog or website that incoming links to them will see an increase in its PageRank. How much is determined by the PageRank of the pages that link to them as well as the number of links on those pages. The higher the PageRank of the linking page, and the lower the number of links on that page, the more PageRank is "sent" to the linked to page.
Every page has a default starting PageRank (I think it is .15).
PageRank is a relative scale (10 is the highest) so you can get more links that send more PageRank to your pages but still see your PageRank drop.
PageRank is no longer an important ranking factor. The time it took me to write this answer is longer than PageRank is worth discussing.

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