Answer:
To find the fraction of the total audience that were students or teachers, you need to add the fractions of students and teachers and simplify the result.
5/12 + 1/8 = (53) / (123) + (16) / (86) = 15/36 + 6/48 = 15/36 + 3/24 = 18/36 + 3/24 = (18+3) / (36+24) = 21/60
So 21/60 of the total audience were students or teachers.