Answer:
Mrs. Garcia's students sold more than Mr. Brown's students
Explanation:
∵ Mr. Brown's 24 students sold the number of magazine subscriptions = 72
∴ magazine subscriptions sold by each Mr. Brown's student =

= 3 per students
∵ Mrs. Garcia's 28 students sold the number of magazine subscriptions = 98
∴ magazine subscriptions sold by each Mrs. Garcia's student =

= 3.5 per students
Mrs. Garcia's homeroom sold more magazine subscriptions per student.