A club consisting of seniors and juniors has 15 members. After seven more seniors and three more juniors join the club, the ratio of juniors to seniors is 2:3. How many juniors are in the club? I guess the thing that screws me up is the ratio part. I don't know what to do. I've found a negative number for J but that can't be right. Right now, I think there are 10 juniors in the club but I really don't know how to prove that. I kind of came upon that number accidentally.