Average Mcqs - Set 9

1)   A batsman in his 17th innings makes a score of 85 and their by increasing his average by 3. What is his average after the 17th innings?

a. 34
b. 35
c. 36
d. 37
Answer  Explanation 

ANSWER: 37

Explanation:
16x + 85 = 17(x + 3)

x = 34 + 3 = 37


2)   The average age of a husband and a wife is 23 years when they were married five years ago but now the average age of the husband, wife and child is 20 years(the child was born during the interval). What is the present age of the child?

a. 1 year
b. 2 years
c. 3 years
d. 4 years
Answer  Explanation 

ANSWER: 4 years

Explanation:
28 * 2 = 56

20 * 3 = 60

4 years


3)   The average age of M boys is ‘b’ years and of ‘n’ girls ‘c’ years. The average age of all together is_________?

a. (mb – nc)/ (m + n) years
b. (mb + nc)/ (m – n) years
c. (mb + nc)/ (m + n) years
d. (mb – nc)/ (m – n) years
Answer  Explanation 

ANSWER: (mb + nc)/ (m + n) years

Explanation:
No explanation is available for this question!


4)   A team of eight entered for a shooting competition. The best marks man scored 85 points. If he had scored 92 points, the average scores for. The team would have been 84. How many points altogether did the team score?

a. 625
b. 665
c. 632
d. 656
Answer  Explanation 

ANSWER: 665

Explanation:
8 * 84 = 672 – 7 = 665


5)   The average salary of workers in an industry is Rs.200 the average salary of technicians being Rs.400 and that of non-technicians being Rs.125. What is the total number of workers?

a. 250
b. 275
c. 550
d. 400
Answer  Explanation 

ANSWER: 550

Explanation:
No explanation is available for this question!


6)   The average age of 8 men increases by 2 years when two women are included in place of two men of ages 20 and 24 years. Find the average age of the women?

a. 36 years
b. 24 years
c. 30 years
d. 18 years
Answer  Explanation 

ANSWER: 30 years

Explanation:
20 + 24 + 8 * 2 = 60/2 = 30


7)   The average of first five prime numbers greater than 20 is____________?

a. 31.00
b. 31.01
c. 32.00
d. 32.2
Answer  Explanation 

ANSWER: 32.2

Explanation:
23 + 29 + 31 + 37 + 41 = 161/5 = 32.2


8)   The average of 9 observations was 9, that of the 1st of 5 being 10 and that of the last 5 being 8. What was the 5th observation?

a. 9
b. 8
c. 7
d. 6
Answer  Explanation 

ANSWER: 9

Explanation:
1 to 9 = 9 * 9 = 81

1 to 5 = 5 * 10 = 50

5 to 9 = 5 * 8 = 40

5th = 50 + 40 = 90 – 81 = 9


9)   The average of 1st 3 of 4 numbers is 16 and of the last 3 are 15. If the sum of the first and the last number is 13. What is the last numbers?

a. 8
b. 6
c. 5
d. 2
Answer  Explanation 

ANSWER: 5

Explanation:
A + B + C = 48

B + C + D = 45

A + D = 13

A – D = 3

A + D = 13

2D = 10

D = 5


10)   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
Answer  Explanation 

ANSWER: 9

Explanation:
3x + 5x + 7x = 45

x =3

3x = 9


11)   The average of first 10 odd numbers is_____________?

a. 11
b. 10
c. 12
d. 17
Answer  Explanation 

ANSWER: 10

Explanation:
Sum of 10 odd no. = 100

Average = 100/10 = 10


12)   The average of first 10 natural numbers is____________?

a. 5
b. 5.5
c. 6.5
d. 6
Answer  Explanation 

ANSWER: 5.5

Explanation:
Sum of 10 natural no. = 110/2 = 55

Average = 55/10 = 5.5


13)   The average of first ten prime numbers which are odd is____________?

a. 12.9
b. 13.8
c. 15.8
d. 17
Answer  Explanation 

ANSWER: 15.8

Explanation:
The odd primes :-

3 , 5 , 7 , 11 , 13 , 17 , 19 , 23 , 29 , 31

Average = 3+5+7+11+13+17+19+23+29+31/10

= 158/10

= 15.8


14)   The average of 11 numbers is 10.9. If the average of first six is 10.5 and that of the last six is 11.4 the sixth number is_____________?

a. 11.0
b. 11.3
c. 11.4
d. 11.5
Answer  Explanation 

ANSWER: 11.5

Explanation:
Sum of 11 numbers = 11×10.9 = 119.9
Sum of 1st 6 numbers = 6×10.5 = 63
So, sum of last 5 numbers = 119.9-63 = 56.9
And sum of last 6 numbers = 6×11.4 = 68.4
Hence sixth number will be = 68.4-56.9= 11.5


15)   The average of first 10 even numbers is___________?

a. 18
b. 22
c. 9
d. 11
Answer  Explanation 

ANSWER: 11

Explanation:
No explanation is available for this question!