git push errors for large files (100M is the limit)

Files larger than 100M are rejected by Github. 

See 

http://git.io/iEPt8g

helen:courses_archives hqin$ git push origin master

Counting objects: 670, done.

Delta compression using up to 8 threads.

Compressing objects: 100% (644/644), done.

Writing objects: 100% (669/669), 789.22 MiB | 916.00 KiB/s, done.

Total 669 (delta 44), reused 0 (delta 0)

remote: error: GH001: Large files detected.

remote: error: Trace: 340050046f102fa5e1320f3fc47e3a80

remote: error: See http://git.io/iEPt8g for more information.

remote: error: File cshlccb2011/cell.cycle.book.chapter.pdf is 172.19 MB; this exceeds GitHub's file size limit of 100 MB

To https://github.com/hongqin/courses_archives.git

 ! [remote rejected] master -> master (pre-receive hook declined)

error: failed to push some refs to 'https://github.com/hongqin/courses_archives.git'

See also
https://help.github.com/articles/working-with-large-files