+312 In Linguistics $101,$ the ratio of the number of juniors to the number of seniors is $3:2$. When twelve more juniors join the class, and one senior drops the class, the ratio of the number of juniors to the number of seniors becomes $2:1$. How many students are in the class after these changes?
+37069 x = ORIGINAL number of students 3/5 are juniors 2/5 are seniors
then add 12 juniors and subtract 1 senior to get :
(3/5 x + 12 ) / (2/5 x -1) = 2/1 cross multiply and solve for x = original # of students = 70
after adding 11 more = 81 students
