Average Problems( Week 23 Evaluation) 1. There are 6 math exams during the semester. Nick has taken 5 exams so far and the scores were 84, 87, 88, 96, and 80. What will Nick need to score on his final math exam to have an average score of 89 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 3 and the third group has 5 numbers with an average of 17. What is the average of all these numbers? 3. The average of 45 numbers is 15. One of numbers was then changed to 1. The average of all the numbers becomes 14 now. What was the number before it was changed? 4. There are 6 numbers. Their average is 14. The average of the first 3 numbers is 15. The average of the last 4 numbers is 14. What is the 3rd 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 17 consecutive numbers is 12. What is the average of the first 11 numbers in the set? 6. The average of 9 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 9th number by 9. What is the average of all the increased numbers? 7. The average score of a math exam is 98 in a class. The average score of the 28 girls in the class is 99 for the exam. The average score of the boys in the class is 96 for the exam. How many boys are there in the class? 8. There are 2 groups of numbers. The first group has 4 numbers with an average of 8. The second group has 2 numbers with an average of 7. What new number can be added to the 2 groups of numbers to make all 7 numbers have an average of 9? 9. There are a total of 8 exams for the chemistry class in the semester. Jennifer got an average of 86 in the first 2 exams and 82 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 85 for the semester? 10. What is the average of all three-digit numbers that are multiples of 13? |