SOLUTION: Sarah has grade of 99 and 69 on her first two tests. If she wants an average of at least 80 after her 3rd test, what score must she make on that test?
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Question 188255: Sarah has grade of 99 and 69 on her first two tests. If she wants an average of at least 80 after her 3rd test, what score must she make on that test? Answer by checkley77(12844) (Show Source):
You can put this solution on YOUR website! (99+69+x)/3>=80
(168+x)/3>=80
168+x>=240
x>=240-168
x>=72 minimum grade for the third test to maintain at least an average of 80.
Proof:
(99+69+72)/3>=80
240/3>=80
80>=80
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