Answer:
18.2% increase
Explanation:
i'm assuming the grades are averages, and if that's the case:
80 + 75 + 95 + 0 + 83 = 333 / 5 = 66.6 (original grade)
80 + 75 + 95 + 91 + 83 = 424 / 5 = 84.8 (new grade)
(to calculate averages, you add all of the numbers up and divide by the total number of numbers)
84.8 - 66.6 = 18.2
(then you subtract the original grade from the new grade to find the percentage increase)
i hope this helps! :)
