SOLUTION: A Student has test scores of 72, 80, 65, 78, and 60. If the final exam counts as one-third of the final grade, what score must the student receive in order to to have a final avera

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: A Student has test scores of 72, 80, 65, 78, and 60. If the final exam counts as one-third of the final grade, what score must the student receive in order to to have a final avera      Log On


   

Question 94796This question is from textbook Fundamentals of Algebra and Trig
: A Student has test scores of 72, 80, 65, 78, and 60. If the final exam counts as one-third of the final grade, what score must the student receive in order to to have a final average of 76? This question is from textbook Fundamentals of Algebra and Trig

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
A Student has test scores of 72, 80, 65, 78, and 60. If the final exam counts as one-third of the final grade, what score must the student receive in order to to have a final average of 76? 

Let x = the grade on the final exam.

The student's average so far is %2872%2B80%2B65%2B78%2B60%29%2F5 = 355%2F5 = 71.
This 71 will count two-thirds, and the final exam one-third. 

So to find the final grade, we add 71 two times and x 
one time and then divide by 3.  So,

final grade = %2871%2B71%2Bx%29%2F3 

So we set this equal to 76

%2871%2B71%2Bx%29%2F3 = 76

%28142%2Bx%29%2F3 = 76

Multiply both sides by 3

142%2Bx = 228

x+=+86

He or she must make 86 on the final exam to average 76
for the course.

Edwin