SOLUTION: susan needs to earn a B in her algebra class. her current test scores are 79, 81, 77 and 80. Her final exam is worth 2 test scores. Susan's average must end up between 85 to 90 (no

Algebra ->  Inequalities -> SOLUTION: susan needs to earn a B in her algebra class. her current test scores are 79, 81, 77 and 80. Her final exam is worth 2 test scores. Susan's average must end up between 85 to 90 (no      Log On


   

Question 1103649: susan needs to earn a B in her algebra class. her current test scores are 79, 81, 77 and 80. Her final exam is worth 2 test scores. Susan's average must end up between 85 to 90 (not inclusive). What range of scores can Susan receive on the final exam to earn a B in the course
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Find the average counting this test twice.
A=%2879%2B81%2B77%2B80%2BT%2BT%29%2F6
A=%282T%2B317%29%2F6
You also know that,
85%3CA%3C90
Substituting,
85%3C%282T%2B317%29%2F6%3C90
510%3C2T%2B317%3C540
193%3C2T%3C223
96.5%3CT%3C111.5
Assuming the max score she can get is 100.
96.5%3CT%3C=100