exam on average part 3

1. In a class of 64 students, the average of the marks obtained is 88. If the top 10 students got on an average 142 marks, find the average of marks obtained by the remaining students :

2. The average score of 55 students in an examination is 88. If the scores of the top four studentsstudents are not considered, then the average of the remaining students drops by 4. If the second highest score is less than 133 and all the students had got integeral scores, find the minimum possible score that could have been scored by the topper:

3. The average salary of 97 workers, 2 assistant managers and one senior manager is Rs. 1500. The salary of each assistant manager is Rs. 3000 and that of the senior manager is Rs. 4000. One assitant manager and the senior manager were replaced by two new people with salaries of Rs/ 3500 and Rs. 4500. Find the new average salary of all the employees:

4. In a account grove, (x + 2) trees yield 60 nuts per year per tree, x trees yield 120 nuts per year per tree and (x – 2) trees yield 180 nuts per year per tree. If the average yield per year per tree be 100. find x.

5. The average age of 24 students and the class teacher is 16 years. If the class teacher’s age is excluded, the average reduces by 1 year. What is the age of the class teacher?

6. The average of x numbers is 3x. If x – 1 is subtracted from each given number. What will be the new average?

7. The average of 40 numbers is 405. If each of the number is divided by 15, find the average of new set of numbers.

8. A batsman in his 19th innings makes a score of 98 run and thereby increases his average by 3. What is his average after 19 innings?

9. A person divides his total route of journey into three equal parts and decides to travel the three parts with speeds of 20, 15 and 10 km/hr respectively. Find his average speed during the whole journey

10. The average salary of the entire staff in a office is ` 130 per month. The average salary of officers is ` 540 and that of non-officers is ` 114. If the number of officers is 16, then find the number of non-officers in the office. (a) 140 (b) 410 (c) 510 (d) 150 111.

11. A car runs for t1 hours at v1 km/ hr, t2 hours at v2 km/hr. What is the average speed of the car for the entire journey?

12. The average of Suresh’s marks in English and History is 55. His average marks in English and Science is 65. What is the difference between the marks which he obtained in History and Science?

13. The average age of the three boys is 15 years. Their ages are in the ratio 3 : 5 : 7. Then the age of the oldest is

14. The population of a town increased by 20% during the first year, by 25% during the next year and by 44% during the third year. Find the average rate of increase during 3 years.

15. An investor earns 3% return on 1/ 4 th of his capital, 5% on 2 /3 rd and 11% on the remainder. What is the average rate of return he earns on his total capital?

16. The average age of a husband and wife was 23 years. When they were married 5 years ago. The average age of the husband, the wife and a child who was born during the interval, is 20 years now. How old is the child now

17. The average height of 40 students is 163 cm. On a particular day, three students A, B, C were absent and the average height of the remaining 37 students was found to be 162 cm. If A, B have equal heights and the height of C be 2 cm less than that of A, find the height of A.

18. The arithmetic mean of the following numbers 1, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6 and 7, 7, 7, 7, 7, 7, 7 is

19. If a, b, c, d, e are five consecutive odd numbers, their average is (a) 5(a+4) (b) abcde 5 (c) 5(a+b+c+d+e) (d) a+4 131.

20. The average of five cosecutive positive intergers is n. If the next two integers are also included, the average of all these integers will (a) increase by 1.5 (b) increase by 1 (c) remain the same (d) increase by 2 133.

21. The average monthly expenditure of a family for the first 4 months ` 2570, for the next 3 months ` 2490 and for the last 5 months ` 3030. If the family saves ` 5320 during the whole year, the average monthly income of the family during the year is

22. If the arithmetic mean of 3a and 4b is greater than 50, and a is twice of b, then the smallest posible integer value of a is

23. In a class, the average score of girls in an examination is 73 and that of boys is 71. The average score for the whole class is 71.8. Find the percentage of girls.

24. A student finds the average of ten, 2-digit numbers. If the digits of one of the numbers is interchanged, the average increases by 3.6. The difference between the digits of the 2-digit numbers is

25. The average age of eleven players of a cricket team decreases by 2 months when two new players are included in the team replacing two players of age 17 years and 20 years. The average age of new player is

26. In a team of 10 persons, nine persons spent ` 40 each for their meals. The 10th one spends ` 9 more than the average expediture of all the 10 persons. The total expediture for their meal was

27. In an exmaination average marks obtained by the girls of a class is 85 and the average marks obtained by the boys of the same class is 87. If the girls and boys are in the ratio 4 : 5. Average marks of the whole class (approximately) is closest to