How much weight do letters of recommendations hold?

Answered

This honestly depends on your college of choice, some of them don't really consider them and they're listed as optional whereas others require them. I only used mine for some of my optional ones when I know its a slightly competitive school. Recommendations make you look better in addition to your academic profile and achievements , but you don't need it for some places if your profile can stand on its own.

Depends on the college. Refer to common data sets of different universities to know the specifics.You won't find a number, though. Common data sets tell you the relative importance of any part of the application as compared to others.

Hope this helps!