SOLUTION: Gina earns score of 65,78,85, and 82 on four tests. What grade must she earn on the next to have an average of 80?
Algebra.Com
Question 587371: Gina earns score of 65,78,85, and 82 on four tests. What grade must she earn on the next to have an average of 80?
Found 3 solutions by solver91311, josmiceli, abush:
Answer by solver91311(24713) (Show Source): You can put this solution on YOUR website!
If you must have an average of 
on 
tests, then the sum of the scores on tests must be 
. Then, if you already know the scores on 
of the tests, add those scores and subtract from . The result will be the score necessary to achieve the desired average.
John
My calculator said it, I believe it, that settles it
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Let = her grade on the next test
From the definition of an average:
She needs a 90 on the next test to average 80
Answer by abush(5) (Show Source): You can put this solution on YOUR website!
(65+78+85+82+n)/5=80
(310+n)/5= 80, multiply both sides by 5
310+n= 400, subtract 310
n=90
RELATED QUESTIONS
gine earns score of 65,78,85 and 82 on four tests. what grade must she earn on the next... (answered by mawskittykat)
Shelia has grades 75,80,and 82.What grade must she earn on her next test to get an... (answered by jim_thompson5910)
a student earned scors of 83, 78, and 77 on three of four tests. what must the student... (answered by Earlsdon)
Jim has grades of 84, 65, and 76 on three math tests. What grade must he obtain on the... (answered by solver91311)
Claire has received scores of 85, 88, 87, and 80 on her algebra tests. What is the... (answered by josmiceli)
Ray had scores of 75, 82, 94 and 77 on his first four math tests. What must he score on... (answered by TimothyLamb)
A student scored the following four math tests: 85, 85, 90, and 95. What must she score... (answered by Fombitz)
a student has earned scores of 80, 81, and 82 on the first 3 of 4 tests. if the student... (answered by maciaemi)
Jim has grades of 84, 65, and 76 on three math tests. What grade must he obtain on the... (answered by rothauserc)
