SOLUTION: Suppose your average, after taking 4 quizzes, is 72 (out of 100). What must your average be on the next 5 quizzes to increase your average to 77 out of 100?

Algebra ->  Average -> SOLUTION: Suppose your average, after taking 4 quizzes, is 72 (out of 100). What must your average be on the next 5 quizzes to increase your average to 77 out of 100?      Log On


   

Question 762898: Suppose your average, after taking 4 quizzes, is 72 (out of 100). What must your average be on the next 5 quizzes to increase your average to 77 out of 100?
Answer by tommyt3rd(5050) About Me  (Show Source):
You can put this solution on YOUR website!
This is a weighted average:

%0D%0A%284%2F9%29%2A72%2B%285%2F9%29%2Ax=77%0D%0A
so that x=81


:)