SOLUTION: There are three exams in a grading period. A student received grades of 82 and 96 on the first two exams. What grade must the student earn on the last exam to earn at least a 90

Algebra ->  Average -> SOLUTION: There are three exams in a grading period. A student received grades of 82 and 96 on the first two exams. What grade must the student earn on the last exam to earn at least a 90       Log On


   



Question 713698:
There are three exams in a grading period. A student received grades of 82 and 96 on the first two exams. What grade must the student earn on the last exam to earn at least a 90 for the grading period?

Answer by checkley79(3341) About Me  (Show Source):
You can put this solution on YOUR website!
(82+96+X)/3>=90
(178+X)/3>=90 CROSS MULTIPLY.
178+X>=3*90
178+X>=270
X=270-178
X=92 ANS FOR THE FINAL TEST.
PROOF:
(82+96+92)/3>=90
270/3>=90
90>=90