help pls its been 30 minutes

Answer:
probability = 6/7
Step-by-step explanation:
a+b+c= 30 students
there are 35 students in total.
=30/35
30/35 fully simplified = 6/7
the probability that a student earns a grade of A, B, or C is 6/7.
also, 6/7 as a decimal rounded the nearest hundreth is 0.86, FYI.