it really depends, but you can expect to attend uni at least 4 days a week. u will usually have 18 hours of classes per week in first yr, and slightly less than that, around 16, in higher yrs.
Yeah, I'm doing Comm (Actuarial)/Sci (Math/Stats). Its a pretty interesting and fun degree, the math subs are especially interesting (and also easier than the actuarial subs). Just watch out for first year, the core commerce courses are pretty boring (to me at least lol).