Pre Algebra
posted by Ry .
In Wilbur's math class, his grade is based on the average score of six tests, each worth 100 points. Wilbur always worries about his grade. He knows that his average on the first four tests is 88.5. What is the lowest average he could get on his next two tests and still average 90 overall?

If you think about the 6 tests as one big test, there are 600 marks overall. Wilbur got 88.5 * 4 = 354 out of the first 400 marks.
Now, to get 90 overall, you need 0.9*600 = 540 out of 600 marks. Now, 540354 = 186, so that he must get 186 out of the next 200 marks. This translates to an mean of 186/2 = 93 for each of the last 2 tests.
Respond to this Question
Similar Questions

Statistics
In your biology class, your final grade is based on several things: a lab score, score on two major tests, and your score on the final exam. There are 100 points available for each score. However, the lab score is worth 25% of your … 
Math
In Wilbur's math class, his grade is based on the average score of six tests, each worth 100 points. Wilbur always worries about his grade. He knows that his average on the four first tests is 88.5. What is the lowest average he could … 
8th grade
At Smart Middle School students are required to take 7 classes each grading period. At the end of each grading period a student is assigned a final grade (A, B, C, D or F) for each class for the grading period. A studentâ€™s overall … 
math
At Smart Middle School students are required to take 7 classes each grading period. At the end of each grading period a student is assigned a final grade (A, B, C, D or F) for each class for the grading period. A studentâ€™s overall … 
math
In your biology class, your final grade is based on several things: a lab score, scores on two major tests, and your score on the final exam. There are 100 points available for each score. However, the lab score is worth 16% of your … 
Statistics
In your biology class, your final grade is based on several things: a lab score, scores on two major tests, and your score on the final exam. There are 100 points available for each score. However, the lab score is worth 15% of your … 
Algebra
In his mathematics class, John has taken 3 tests, each worth 20% of his total grade. His grades on those tests were 92%,83%,and 85%. He has an 100% average on his homework, worth 10% of his grade. All that remains is a final exam worth … 
Math
In your class, you have scores of 73,85,76, and 92 on the first four of five tests. To get a grade of Upper C, the average of the first five tests scores must be greater than or equal to 70 and less than 80. a) Solve an inequality … 
Math Help
In three math tests, you have scored 91,95 and 88 points. You are about to take your next test. Suppose you want to have an average score of at least 90 points after all four tests. Explain a method you could use to find the score … 
Math
In math class, a student has an average grade of 85% for five tests so far. What grade must that student earn on the next test to reach an average grade of 90% for all six tests?