Question 942633: on the first four exams, your grades are 82, 75, 80, and 92. there is still a final exam, and it counts as two grades. you are hoping to earn a b in the course: this will occur if the average of your six exam grades is greater than or equal to 80 and less than 90. what range of grades on the final exam will result in earning a b? use interval notation to express this range
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! on the first four exams, your grades are 82, 75, 80, and 92. there is still a final exam, and it counts as two grades. you are hoping to earn a b in the course: this will occur if the average of your six exam grades is greater than or equal to 80 and less than 90. what range of grades on the final exam will result in earning a b? use interval notation to express this range
-------
Solve::
(82+75+80+92+2x)/6 = 80
329 + 2x = 480
2x = 151
x = 75.5
------
Solve::
(329+2x)/6 = 90
329+2x = 6*90
329 + 2x = 540
2x = 211
x = 105.5
-----
Note:: Since the score on the final cannot exceed 100,
Ans:: 75.5<= score <=100
----------------
Cheers,
Stan H.
-----------
2x = 311
x = 155.5
|
|
|
