We conclude that the starting average grade is 79.17%
<h3>
How to write the equation and solve it?</h3>
There are 50 students, let's say that the grades are measured between 1% and 100%.
And the average grade of the 50 students is A.
We know that after it increased by 20%, the average of the grades is 95.
Then we just need to solve the percentage equation:
95 = A*(1 + 20%/100%) = A*(1.2)
95/1.2 = A = 79.17
We conclude that the starting average grade is 79.17%
If you want to learn more about percentages:
brainly.com/question/843074
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