SOLUTION: Here is the question? On five exams, Alex has scored 84, 86, 71, 91, and 98 points out of 100. He wants to earn at least a B in the course, which corresponds to an overall avera

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Question 148572This question is from textbook
: Here is the question?
On five exams, Alex has scored 84, 86, 71, 91, and 98 points out of 100. He wants to earn at least a B in the course, which corresponds to an overall average grade of 82 or better. Out of 100 points, what is the minimum number of points Alex must earn on the final exam to achieve this goal?
Now i think on this you need to add up 84, 86, 71, 91, and 98 and than divide them by 5. This will give you the answer..Am i on the right track or totally off? Thank you This question is from textbook

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Let x=score on sixth exam

So the average A of all 6 exams are


A=%2884%2B86%2B71%2B91%2B98%2Bx%29%2F6


Since the average must be greater than or equal to 82, this means that the right side is greater than or equal to 82

%2884%2B86%2B71%2B91%2B98%2Bx%29%2F6%3E=82 Set the right side greater than or equal to 82


84%2B86%2B71%2B91%2B98%2Bx%3E=492 Multiply both sides by 6.


x%2B430%3E=492 Combine like terms on the left side.


x%3E=492-430 Subtract 430 from both sides.


x%3E=62 Combine like terms on the right side.


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Answer:

So the answer is x%3E=62 which means that the student must get a 62 or better on the 6th exam in order to get an overall average grade of 82 or better.