SOLUTION: iN YOUR ECONOMICS CLASS YOU HAVE SCORES OF 68, 82, 87, AND 89 ON THE FIRST FOUR OF FIVE TEST. TO GET A GRADE OF B THE AVERQAGE OF THE FIRST FIVE TEST SCORES MUST BE GREATER THAN OR

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Question 97428: iN YOUR ECONOMICS CLASS YOU HAVE SCORES OF 68, 82, 87, AND 89 ON THE FIRST FOUR OF FIVE TEST. TO GET A GRADE OF B THE AVERQAGE OF THE FIRST FIVE TEST SCORES MUST BE GREATER THAN OR EQUAL TO 80 AND LESS THAN 90. SOLVE AN INEQUALITY TO FIND THE RANGE OF THE SCORES THAT YOU NEED ON THE TEST TO GET A B
Answer by Earlsdon(6294) (Show Source):
You can put this solution on YOUR website!
To find the average score (A) of the first five tests, you'll add the scores and divide by 5.
where x is the score on the fifth test.
Now you need this average (A) to be at least 80 () but less than 90 ().
You can write the inequality thus:
To solve this, you'll simplify the numerator.
Now you'll multiply everything by 5.
Simplify.
Now you'll subtract 326 from everything.
Simplify.
Read this as: x is at least 74 but less than 124.
The range of scores needed to get a B average is at least 74 but less than 124.