I doubt that there are 500 people doing a Chem major. I think at the current moment in time there may actually be 2000 people in the course. However, the best number estimate for HSFY would be next semester in the Epidemiology paper.
Given that last year PHSI191 had 1250 students, there would have been around 1200 HSFY students. By second semester HEAL192 had enough dropouts to fit into 2 streams at St. David = 1100 students.
This number of 1200 also appears to be pretty consistent - at the HSFY prelim lecture this year they were apparently told that there were 1200 students this year as well.
CHEM191 is the only first semester level 100 chem paper, so it is taken by anyone interested in chemistry (which would be quite a few), chem majors, and chem minors, along with those in other courses (e.g. food science) that require it.
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