## WBCS MAIN PAPER VI : MATHEMATICS - AVERAGE AND SUMMATION

- WBCS Main Examination Paper - VI (Arithmetic and Test of Reasoning) - 2021
- WBCS Main Examination Paper - VI (Arithmetic and Test of Reasoning) - 2020
- WBCS Main Examination Paper - VI (Arithmetic and Test of Reasoning) - 2019
- WBCS Main Examination Paper - VI (Arithmetic and Test of Reasoning) - 2018
- WBCS Main Examination Paper - VI (Arithmetic and Test of Reasoning) - 2017
- WBCS Main Examination Paper - VI (Arithmetic and Test of Reasoning) - 2016
- WBCS Main Examination Paper - VI (Arithmetic and Test of Reasoning) - 2015
- WBCS Main Examination Paper - VI (Arithmetic and Test of Reasoning) - 2014

1.The average of first ten prime numbers which are odd is** (A) 12.9** (B) 13.8 (C) 15.8 (D) 17

2.The average of first 10 even numbers is (A) 18 (B) 22 (C) 9 **(D) 11 **

3.The average age of three boys is 15 years and their ages are in proportion 3: 5:7. What is the age in years of the youngest boy?

(A) 15 **(B) 9 **(C) 18 (D) 21

4.The average of first 10 natural numbers is (A) 5 **(B) 5.5** (C) 6.5 (0) 6

5.If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55, 60, then the average marks of all the students is

(A) 53.33 **(B) 54.68 **(C) 55 (D) None of the above

1.Average age of 8 sons of a family is 12 years. Average age of the sons together with their parents is 21 years. If the father is older than the mother by 8 years, then the age of the mother is

(A) 48 years (B) 53 years ** (C) 60 years ** (D) 62 years

2.The average weight of 8 persons increases by 2.5 kg when a new person comes in place of one of them weighing 65 kg. What might be the weight of the new person ?

(A) 76 kg (B) 5 kg **(C) 85 kg** (D) None of the above

3.What is the number of triangles in the following figure ?

(A) 10 (B) 9 **(C) 11** (D) 12

4.If the average of a, b, c is 15, the average of b, c, d is 12 and the average of a, d is 13, the value of d is

(A) 34 (B) 30 (C) 24 **(D) 10**

1.There are five positive observations. Average of the first three observations is 8 and that of the last three observations is 6. If the average of all five observations is 6, what is the third observation ?

(A) 10 (B) 8 **(C) 12** (D) 14

1.The mean of 19 observations is 4. If one more observation of 24 is added to the data, the new mean will be

**(A) 5** (B) 6 (C) 4 (D) 7

2.The average of three numbers is 28. The first number is half of the second and the third number is twice the second. The third number is

**(A) 48** (B) 18 (C) 24 (D) 36

3.The average weight of x, y, z is 45 kg. If the average weight of x and y be 40 kg and that of y and z be 43 kg, then the weight of y is

(A) 20 kg (B) 26 kg **(C) 31 kg** (D) 17 kg

1.The average of first 100 natural numbers is-

(A) 50 **(B) 50.5** (C) 51 (D) 51.5

2.A man bought 5 shirts at Rs. 450 each, 4 trousers at Rs.750 each and 12 pairs of shoes at Rs. 750 each. The average expenditure per article is :

**(A) Rs. 678.50** (B) Rs. 800 (C) Rs. 900 (D) Rs. 1,000

3.The average score of 10 students in a test is 25. The lowest score is 20. Then the highest score is at most-

(A) 30 **(B) 70** (C) 75 (D) 100

1.If the average of first 21 natural numbers is 11, average of first 20 natural numbers will be

(A) 9 (B) 9.5 (C) 10 **(D) 10.5**

2.Out of 11 numbers average of first 6 numbers is 8.5 and the average of last six numbers is 6.5. If the average of 11 numbers is 8, the sixth number is

(A) 1 **(B) 2** (C) 3 (D) 4

3.Average of five consecutive Odd numbers is 15. The least number is

**(A) 11** (B) 13 (C) 15 (D) 17

4.The average of two numbers is xy. If one number is X, the other number is

(A) y/2 (B) y **(C) (2xy - x)** (D) x(y - 1)

5.The mean of five numbers is 18. If one number is excluded, their mean is 16. The excluded number is

(A) 25 **(B) 26** (C) 27 (D) 30

1.The average marks of boys in a class is 52 and that of girls is 42 . The average marks of boys and girls combined is 50. What is the percentage of boys in the class ?

(A) 70% (B) 75% **(C) 80%** (D) 82%

2.The average of first 51 natural numbers is 26. What is the average of first 50 natural numbers ?

(A) 24 (B) 24.5 ** (C) 25 ** (D) 25.5

3.The mean proportion between 9 and 16 is

(A) 12.5 **(B) 12 ** (C) 5 (D) None of the above

4.Average weight of some students is 55 kg.; of them average weight of 20 students is 60 kg. and average weight of remaining students is 51 kg. What is the number of students ?

(A) 30 (B) 35 (C) 40 **(D) 45**

5.A student wrote 54 instead of 45 by mistake. As a result he got the average of 5 numbers as 52. What is the correct average of the numbers ?

(A) 48 (B) 48.8 (C) 50 **(D) 50.2**