SOLUTION: Professor Williamson counts his midterm as 2/3 of the grade and his final as 1/3 of the grade. Wendy scored only 48 on the midterm. What range of scores on the final exam would

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Professor Williamson counts his midterm as 2/3 of the grade and his final as 1/3 of the grade. Wendy scored only 48 on the midterm. What range of scores on the final exam would       Log On


   

Question 164834: Professor Williamson counts his midterm as 2/3 of the grade and his final as 1/3 of the grade.
Wendy scored only 48 on the midterm. What range of scores on the final exam would put Wendy’s average
between 70 and 79 inclusive? Compare to the previous exercise.
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!

First, let's compute to have an ave. of 70:
%282%2F3%29MT%2B%281%2F3%29FE=70
%282%2F3%29%2848%29%2B%281%2F3%29%28FE%29=70
%2896%2F3%29%2B%281%2F3%29%28FE%29=70
%281%2F3%29FE=70-%2896%2F3%29=70-%28cross%2896%2932%2Fcross%283%29%29
%281%2F3%29FE=70-32=38, cross multiply
FE=38%2A3=114
Next, ave. of 79:
%282%2F3%29%2848%29%2B%281%2F3%29FE=79
%2896%2F3%29%2B%281%2F3%29FE=79
%281%2F3%29FE=79-%2896%2F3%29=79-%28cross%2896%2932%2Fcross%283%29%29
%281%2F3%29FE=79-32=47, cross multiply
FE=47%2A3=141
Therefore, the Final Exam should be in the range of highlight%28114-141%29 to have an average of 70-79 inclusive.
thank you,
Jojo