Walking across campus, a student interviewed a group of students. 35% of the students took a finance class last semester, 45% took a marketing class last semester, and 50% took neither a finance nor a marketing class last semester. What percent of the students in the group took both a finance and a marketing class?  Choose the correct choice: A) 40% B) 30% C) 25% D) 15% E) 10%
{Total} = {finance} + {marketing} - {both} + {neither}   100 = 35 + 45 - {both} + 50   {both} = 30%.   The answer is 30%.
<result>B</result>
Walking across campus, a student interviewed a group of students. 35% of the students took a finance class last semester, 45% took a marketing class last semester, and 50% took neither a finance nor a marketing class last semester. What percent of the students in the group took both a finance and a marketing class?