



 
Hi Janna, Suppose that S is the sum of your scores on the first 4 quizzes then S/4 = 71 so S = 471 = 284. Suppose that the sum of your grades on the next 5 quizzes is T then the total of your grades on all 9 quizzes is S + T = 284 + T. You want the average on all 9 quizzes to be 81 so (284 + T)/9 = 81. Solve for T. What is your average on quizzes 5 to 9? Penny  


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