To solve this question, first start by finding Jim’s current average in the class (assuming that the assignments aren’t weighted.)
Add all of the test scores together:
95 + 82 + 84 + 91 = 352
Now, find the average by dividing by the total number of test scores. In this case, we have four test scores.
So:
352/4 = 88
So Jim’s current average in the class is an 88%.
To find the lowest grade Jim can get to get a 90 A in the class, you can plug in numbers and performs the same calculation again, only dividing by 5 rather than 4, as there are now 5 test scores.
The lowest value Jim can get that gives him an A is a 98.
That gives an added total of 450, which after divided by the total number of test scores (5) Jim receives a 90 in the class.
I hope this helps! :)