Average Problems( Week 23 Evaluation) 1. There are 6 math exams during the semester. Ben has taken 5 exams so far and the scores were 84, 90, 82, 88, and 96. What will Ben need to score on his final math exam to have an average score of 87 for the semester? 2. There are 3 groups of numbers. The first group has 3 numbers with an average of 4. The second group has 2 numbers with an average of 5 and the third group has 5 numbers with an average of 11. What is the average of all these numbers? 3. The average of 17 numbers is 9. One of numbers was then changed to 10. The average of all the numbers becomes 8 now. What was the number before it was changed? 4. There are 8 numbers. Their average is 12. The average of the first 6 numbers is 13. The average of the last 3 numbers is 14. What is the 6th number? 5. Consecutive numbers are natural numbers that follow in order, such as 1,2, 3, 4, 5,..., and so forth. Suppose the average of 13 consecutive numbers is 11. What is the average of the first 11 numbers in the set? 6. The average of 7 numbers is 19. Let the 1st number increases by 1, the 2nd number by 2, the 3rd number by 3, the 4th number by 4 ... and the 7th number by 7. What is the average of all the increased numbers? 7. The average score of a math exam is 96 in a class. The average score of the 32 girls in the class is 97 for the exam. The average score of the boys in the class is 94 for the exam. How many boys are there in the class? 8. There are 2 groups of numbers. The first group has 5 numbers with an average of 5. The second group has 6 numbers with an average of 4. What new number can be added to the 2 groups of numbers to make all 12 numbers have an average of 5? 9. There are a total of 8 exams for the chemistry class in the semester. Nancy got an average of 79 in the first 2 exams and 83 in the following 4 exams. What is the average she will need to score in the remaining exams in order to get an average of 80 for the semester? 10. What is the average of all three-digit numbers that are multiples of 11? |