Students grade in a course is the average of 4 test grades a

Students grade in a course is the average of 4 test grades and a final exam that is worth twice as much as each test. Suppose a student has test grades of 90, 89, 80, and 91. Write an equation to model this situation where is the student\'s grade on the final exam and y is the student\'s average for the course. Then find the score they will need to receive on their final exam if they want to have a grade for the course. Final exam score needed =

Solution

scores: 90, 89, 80 and 91

Avg : (90+89+80+91+x)/(4+2) = y

350+x = 6y

If y = 88

350 +x = 6*88

x = 178 in final test