SOLUTION: A student has an 83 average. Her final exam will count as 1/3 of her grade. What does she need to make on her final to pass the class with a 70 average?

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Question 743338: A student has an 83 average. Her final exam will count as 1/3 of her grade. What does she need to make on her final to pass the class with a 70 average?
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
A student has an 83 average. Her final exam will count as 1/3 of her grade. What does she need to make on her final to pass the class with a 70 average?
Her final exam will count as 1/3 of her grade.  Therefore,

her 83 average will count as 2/3 of her grade.

Let x = her final exam grade

Then,

%28matrix%285%2C1%2C%0D%0A%0D%0A2%2F3%2Ctimes%2Cher%2C83%2Caverage%29%29%22%22%2B%22%22%28matrix%286%2C1%2C%0D%0A%0D%0A1%2F3%2Ctimes%2Cher%2Cx%2Cexam%2Cgrade%29%29%22%22=%22%2270


     expr%282%2F3%29%2A83%22%22%2B%22%22expr%281%2F3%29x%22%22=%22%2270

Multiply every term by LCD = 3

     3%2Aexpr%282%2F3%29%2A83%22%22%2B%22%223%2Aexpr%281%2F3%29x%22%22=%22%223%2A70

     cross%283%29%2Aexpr%282%2Fcross%283%29%29%2A83%22%22%2B%22%22cross%283%29%2Aexpr%281%2Fcross%283%29%29x%22%22=%22%22210

     2%2A83%22%22%2B%22%22x%22%22=%22%22210

     166 + x = 210
           x = 44

Edwin