In a school, the final grades of a subject for an academic year are calculated, based on the grades that a student gets in his assignments, tests and a final exam. Assignments have the weightage of 28%, tests of 22%, and the final exam of 50%. If a student has an assignment grade of 80, a test grade of 75, an exam grade of 86, then his overall grade for the year is _________.

81.9

Grade from assignment = \(\frac{28}{100}\) × 80

= \(\frac{28}{5}\) × 4  = 22.4

Grade from test = \(\frac{22}{100}\) × 75

= \(\frac{22}{4}\) × 3 = 16.5

Grade from Final exam = \(\frac{50}{100}\) × 86

= \(\frac{1}{2}\) × 86 = 43

Then overall grade = 22.4 + 16.5 + 43 = 81.9