In a Don Bosco college students, 80 percent are third year students and 90 percent are not second-year students. What fraction of those students who are not third-year students are second-year students?  Choose the correct choice from the following choices
A) 3/4  B) 2/3  C) 4/7  D) 1/2  E) 3/7
= 10/20. = 1/2   my answer is 1/2 too
<result>D</result>
In a Don Bosco college students, 80 percent are third year students and 90 percent are not second-year students. What fraction of those students who are not third-year students are second-year students?