Answer:
82.2 (the last option)
Step-by-step explanation:
Weighted Sum
When we get a sequence of values a,b,c... and we want to know the sum of all but with different percent weights pa,pb,pc... where pa+pb+pc...=100%, we compute the weighted sum as
S=a.pa+b.pb+c.pc...
The student got this final grades: tests 86, project 76, reviews 77 and their relative weights are tests 60% (0.6), book review 20% (0.2), project 20% (0.2)
The final grade is
s=86(0.6)+76(0.2)+77(0.2)
S=82.2
