In Brianna’s school, grades are calculated as follows: 60% from tests, 25% from homework, and 15% from in-class assignments. (Grades can be considered as expected values of a continuous random variable, but not necessarily normally distributed.) If Brianna’s test total is 84 out of 100, her homework score is 91 out of 100, and her in-class grade is 75 out of 100, what is her grade average? Enter your answer up to one decimal place.