No, because there are other factors mixed in, such as requiring a minimum number of upvotes by contributors not recognised as being in a voting ring, and beating the "gravity" factor. There are also penalties applied for certain types of posts and sources, boosts applied for certain types of posts, and penalties for some conditions. For example, when a post hits 40 posts, if the number of comments exceeds the number of points, a "probable flame war" penalty is applied.

So it's not the case that posts from the new page "get mixed in" to the Front Page, they get there on merit based on getting enough votes in a short enough time. To say they get "mixed in" implies that they are simply plucked from the "Newest" page and put on the Front Page regardless of votes. And that's not the case.

Usually.