SOLUTION: A student score on the first 3 class was 65,78 & 84.what range of the score on the forth test will give the student an average that less than 80 but not less than 70 on the forth

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Question 821439: A student score on the first 3 class was 65,78 & 84.what range of the score on the forth test will give the student an average that less than 80 but not less than 70 on the forth test.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A student score on the first 3 class was 65,78 & 84.what range of the score on the forth test will give the student an average that is less than 80 but not less than 70 on the forth test.
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Equation:
70 < (65+78+84+x)/4 < 80
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280 < 227+x < 320
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Ans:: 53 < x < 93
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Cheers,
Stan H.
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