Both are fine schools that can get you where you need to go. Here are some general comments:
–I’m not so sure what an “invitation” means in terms of getting meaningful aid etc. To me, it looks like the candidates choice application is simply an alternate application sent to people who have expressed interest in RPI. These are pretty common and are meant to increase applications to the school http://admissions.rpi.edu/undergraduate/admission/freshman/application.html
–Look into which school has more overall aid to internationals.
–RPI is more of a technical/STEM-engineering based school while Bucknell is more of an all-around school with excellent engineering, business, and humanities programs.
-There is Greek life at both schools – I know that Bucknell is pretty Greek-oriented, not sure about RPI.
–RIP is a mid-sized university, Bucknell is a LAC - do you have a preference?
–And hopefully you saw these:
http://admissions.rpi.edu/undergraduate/admission/international/
http://www.bucknell.edu/admissions/international-admissions/paying-for-bucknell.html
–Since finances are an issue, I hope you are researching alternatives in India as well in case you don’t get the aid needed to come to the US for your undergraduate education.
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