That is not correct. It depends on the subject of the site Plus inbound links.
To get a
PR 4 page for "Mexia Real Estate"(the town where anna nicole smith is from) would only take 200 proper links. But for Houston Real estate it will take 2 to 5 k inbound links.
So, if you can reach
PR 4 for one phrase, by what you have stated, you should be able to get
PR 4 for any site with 200 links, and that is 100 % false.
The title and content(what the site is about) has a major effect on how many links are needed to get to any specific
PR for a page. and you also stated that it is the
PR of the website, but this is a broad statement also as each page is assigned it's own
PR.
The numbers of inbound and outbound links on any given page also affects the
pr as well as the
PR of the
page the link comes from. The title of the page the link comes from and the content of the page the link comes from.
And there are numerous other factors involved, too many to cover right here.