The answer is -ARGUMENTS-. I got it correct on my exam.
Victor assaults his investigations with excitement and, overlooking his public activity and his family far away in Geneva, gains quick ground. Later, Ardently dedicating himself to this work, he ignores everything else; family, companions, studies, and public activity, and becomes progressively pale, desolate, and fixated.
Well you could solve by cross multiplying 66 and 2/3 (into an improper fraction) multiplied by the reciprocal of 30, but 66 and 2/3 means 2/3 (1/3 equals 33 1/3 %) so then you can divide 30 by 3, which is 10, and then multiply by 2 to get 20. So, 66 and 2/3 of 30 is 20. Hope that helped!