Every student in a room is either a junior or a senior. There is at least one junior and at least one senior in the room. If 4/5 of the juniors is equal to 1/2 of the seniors, what fraction of the students in the room are juniors?  Pick one: A) 13/20 B) 11/3 C) 5/13 D) 12/17 E) 17/20
Let total number of juniors= J   total number of seniors =S   (4/5) J = (1/2) S   =&gt; S = 8/5 J   Total number of students = J+S = (13/5) J   Fraction of the students in the room are juniors = J/(J+S) = J/[(13/5) J]   =5/13   Answer 5/13
<result>C</result>
Every student in a room is either a junior or a senior. There is at least one junior and at least one senior in the room. If 4/5 of the juniors is equal to 1/2 of the seniors, what fraction of the students in the room are juniors?