209 + Interview Questions in AVERAGE in Mathematics Page 1 InterviewSolution

1.	A man bought 13 articles at Rs 70 each. 15 at Rs 60 each and 12 at Rs 65 each. The average price per article is1). Rs60.252). Rs64.753). Rs65.754). Rs62.25
Answer» Rs64.75 is the CORRECT ANSWER as PER the SSC answer KEY

Discussion

2.	The average age of 45 persons is decreased by $\frac{1}{9}$ year when one of them of 60 years is replaced by a new comer. Then the age of the new comer is :1). 45 years2). 55 years3). 59 years4). 49 years
Answer» OPTION 2 is the RIGHT ONE

Discussion

3.	The average mathematics marks of two Sections A and B of Class IX in the annual examination is 74. The average marks of Section A is 77.5 and that of Section B is 70. The ratio of the number of students of Section A and B is1). 7:82). 7:53). 8:74). 8:5
Answer» OPTION 3 is the CORRECT answer as PER the answer KEY

Discussion

4.	A student finds the average of 10, 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 is1). 42). 33). 24). 5
Answer» HELLO, 4 is CORRECT

Discussion

5.	If the average of eight consecutive even numbers be 93.then the greatest number among them is1). 1002). 863). 1024). 98
Answer» option 1 is the CORRECT answer as PER the answer KEY

Discussion

6.	Out of seven given numbers,the average of the first four numbers is 4 and that of the last four numbers is also 4.If the average of all the seven numbers is 3.fourth number is1). 32). 43). 74). 11
Answer» I THINK 11 is RIGHT

Discussion

7.	The average of six numbers is 20. If one number is removed, the average becomes 15. What is the number removed 1). 52). 353). 1124). 45
Answer» 45 is the correct answer as per the SSC answer KEY

Discussion

8.	The mean of 9 observations is 16. One more observation is included and the new mean becomes 17.The 10th observation is1). 92). 163). 264). 30
Answer» OPTION 3 is the RIGHT ANSWER

Discussion

9.	What is the average of the first six (positive) odd numbers each of which is divisible by 71). 422). 433). 474). 49
Answer» OPTION option 1 is the CORRECT ANSWER

Discussion

10.	A man’s pension on retirement from service is equal to half the average salary during last 3 years of his service.His salary from 1-1-1983 is Rs380 per month with increment of Rs40 due on 1-10-83, 1-10-84 and 1-10-85.If he retires on 1-1-86,what pension does he draw per month1). 2052). 2153). 2254). 230
Answer» OPTION 2 is the RIGHT ANSWER

Discussion

11.	The average of 12 numbers is 15 and the average of the first two is 14.What is the average of the rest1). 152). $15\frac{1}{5}$3). 144). $14\frac{1}{5}$
Answer» If we observe the average of 12 NUMBERS is 15.But the average of first 2 is 14The average of rest must be GREATER than 15 there is only ONE OPTION

Discussion

12.	Three numbers are such that the average of first two numbers is 2,the average of the last two numbers is 3 and the average of the first and the last numbers is 4,then the average of three numbers is equal to1). 22). 3.53). 34). 2.5
Answer» RIGHT ANSWER for this QUESTION is 3.5

Discussion

13.	If out of 10 selected students for an examination, 3 were of 20 years, age, 4 of 21 and 3 of 22 years, the average age of the group is1). 22 years2). 21 years3). 21.5 years4). 20 years
Answer» This QUESTION was ASKED some where in previous year PAPERS of ssc, and CORRECT answer was option 2

Discussion

14.	The average of 10 numbers is calculated as 15. It is discovered later on that while calculating the average one number, namely 36, was wrongly read as 26.The correct average is1). 202). 183). 164). 14
Answer» it from PREVIOUS year ssc papers, 18 is the right answer

Discussion

15.	Six friends have an average height of 167 cm .A boy with height 162 cm leaves the group. Find the new average height.1). 168cm2). 166cm3). 169cm4). 167cm
Answer» 168cm is the correct ANSWER. $ \large \frac{(6 \TIMES 167) - 162}{5} = 168 $

15.

Six friends have an average height of 167 cm .A boy with height 162 cm leaves the group. Find the new average height.1). 168cm2). 166cm3). 169cm4). 167cm

Answer»

168cm is the correct ANSWER.

$ \large \frac{(6 \TIMES 167) - 162}{5} = 168 $

Discussion

16.	The average age of Ram and two children is 17 years and the average age of Ram's wife and the same children is 16 years. If the age of Ram is 33 years, the age of his wife is (in years):1). 312). 323). 354). 30
Answer» RIGHT ANSWER is 30

Discussion

17.	From a class of 24 boys, a boy , aged 10 years, leaves the class and in his place a new boy is admitted. As a result, the average age of the class is increased by 2 months. What is the age of the new boy 1). 12 years2). 15 years3). 14 years4). 13 years
Answer» I THINK 15 YEARS is RIGHT

Discussion

18.	a,b,c,d,e,f,g are consecutive even numbers.J,k,l,m,n are consecutive odd numbers.The average of all the numbers is1). $3(\frac{a+n}{2})$2). $\frac{l+d}{2}$3). $\frac{a+b+m+n}{4}$4). $\frac{j+c+n+g}{4}$
Answer» HELLO, $\FRAC{l+d}{2}$ is CORRECT

Discussion

19.	There were 35 students in a hostel. If the number of students is increased by 7 the expenditure on food increases by Rs.42 per day while the average expenditure of students is reduced by Rs.1. What was the initial expenditure on food per day 1). 4002). 4323). 4424). 420
Answer» This QUESTION was asked some where in PREVIOUS year papers of ssc, and CORRECT answer was OPTION 4

Discussion

20.	The average income of 40 persons is Rs 4200 and that of another 35 persons is Rs 4000. The average income of the whole group is:1). Rs 41002). Rs $4106\frac{1}{3}$3). Rs $4106\frac{2}{3}$4). Rs $4108\frac{1}{3}$
Answer» RS $4106\frac{1}{3}$ : - OPTION 3

Discussion

21.	In an examination, the average of marks was found to be 50. For deducting marks for computational errors, the marks of 100 candidates had to be changed from 90 to 60 each and so the average of marks down to 45. The total number of candidates, who appeared at the examination, was1). 6002). 3003). 2004). 150
Answer» OPTION 1 is the ANSWER

Discussion

22.	A student finds the average of ten 2-digit numbers. While copying numbers, by mistake, he writes one number with its digits interchanged. As a result his answer is 1.8 less than the correct answer.The difference of the digits of the number,in which he made mistake,is1). 22). 33). 44). 6
Answer» OPTION 1 : 2 is CORRECT

Discussion

23.	The average age of four brothers is 12 years. If the age of their mother is also included, the average is increased by 5 years. The age of the mother (in years)is :1). 37 years2). 43 years3). 48 years4). 53 years
Answer» CORRECT ANSWER is: 37 YEARS

Discussion

24.	Find the average of 1.11, 0.01,0.101, 0.001, 0.111). 0.26642). 0.25543). 0.12644). 0.1164
Answer» ANSWER for this QUESTION is 0.2664

Discussion

25.	The average of 6 observations is 45.5. If one new observation is added to the previous observations,then the new average becomes 47.The new observation is1). 582). 563). 504). 46
Answer» OPTION 2 is the RIGHT ANSWER

Discussion

26.	The average of marks obtained by 120 candidates in a certain examination is 35.If the average marks obtained by passed candidates are 39 and those of the failed candidates are 15. what is the number of candidates who passed the examination 1). 1002). 1203). 1504). 140
Answer» I THINK OPTION 1 is the RIGHT ANSWER

Discussion

27.	The average of marks scored by the students of a class is 68. The average of marks of the girls in the class is 80 and that of boys is 60. What is the percentage of boys in the class 1). 40 %2). 60 %3). 65 %4). 70 %
Answer» 60 % : SEEMS CORRECT

Discussion

28.	The average of 30 results is 20 and the average of other 20 results is 30. What is the average of all the results 1). 242). 483). 254). 50
Answer» 24 : SEEMS CORRECT

Discussion

29.	The average age of P, Q and R is 5 years more than R's age. If the total ages of P and Q together is 39 years, then R's age is1). 12 years2). 24 years3). 16 years4). 14 years
Answer» 12 YEARS is the ANSWER

Discussion

30.	The average of 9 integers is found to be 11. But after the calculation,it was detected that, by mistake,the integer 23 was copied as 32. while calculating the average. After the due correction is made, the new average will be1). 102). 93). 10.14). 9.5
Answer» 10 : - is CORRECT HENCE OPTION 1

Discussion

31.	The average of marks in Mathematics for 5 students was found to be 50. Later,it was discovered that in the case of one student the marks 48 were misread as 84.The correct average is :1). 40.22). 40.83). 42.84). 48.2
Answer» I have READ it SOMEWHERE 40.8 is CORRECT

Discussion

32.	Average of n numbers is a .The first number is increased by 2,second one is increased by 4,the third one is increased by 8 and so on. The average of the new numbers is1). $a+\frac{2^{n-1} -1}{n}$2). $a+2\frac{2^{n}-1}{n}$3). $a+\frac{2^{n-1}}{n}$4). $a+\frac{2^{n}-1}{n}$
Answer» CORRECT ANSWER is: OPTION 2

Discussion

33.	The average of 30 numbers is 40 and that of other 40 numbers is 30. The average of all the numbers is1). $34\frac{2}{7}$2). 353). 344). 34.5
Answer» OPTION 1 : $34\frac{2}{7}$ is CORRECT

Discussion

34.	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 is1). 42). 53). 144). 20
Answer» 5 : OPTION 2 is the CORRECT ANSWER

Discussion

35.	4 boys and 3 girls spent Rs120 on the average, of which boys spent Rs150 on the average. Then the average amount spent by the girls is1). Rs802). Rs603). Rs904). Rs100
Answer» it from previous year ssc papers, RS80 is the RIGHT ANSWER

Discussion

36.	The average age of a cricket team of 11 players is the same as it was 3 years back because 3 of the players whose current average age of 33 years were replaced by 3 youngsters. The average age of the newcomers is1). 23 years2). 21 years3). 22 years4). 20 years
Answer» HELLO, 21 YEARS is CORRECT

Discussion

37.	If average of 20 observations $x_{1}$,$x_{2}$.......$x_{20}$ is y ,then the average of $x_{1}- 101$, $x_{2}- 101$,$x_{3}- 101$, .....,$x_{20}- 101$ is1). y-202). y-1013). 20y4). 101y
Answer» OPTION 2 is the RIGHT ANSWER

Discussion

38.	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 is1). 17 years 1 month2). 17 years 7 month3). 17 years 11 month4). 18 years 3 month
Answer» CORRECT ANSWER was OPTION 2

Discussion

39.	If the average marks of three batches of 55, 60 and 45 students respectively is 50,55 and 60,then the average marks of all the students is1). 54.682). 53.333). 554). None of these
Answer» RIGHT ANSWER for this QUESTION is 54.68

Discussion

40.	The average age of eleven cricket players is 20 years. If the age of the coach is also included, the average age increases by 10%. The age of the coach is1). 48 years2). 44 years3). 40 years4). 36 years
Answer» RIGHT ANSWER for this QUESTION is 44 YEARS

Discussion

41.	Of the three numbers,the first number is twice of the second and the second is thrice of the third number.If the average of these 3 numbers is 20,then the sum of the largest and smallest numbers is1). 242). 423). 544). 60
Answer» 42 : OPTION 2 is the CORRECT ANSWER

Discussion

42.	The average age of a husband and his wife was 23 years at the time of their marriage. After five years they have a one year old child .The average age of the family now is1). 29.3 years2). 19 years3). 23 years4). 28.5 years
Answer» 19 YEARS is the correct ANSWER as per the ssc answer KEY

Discussion

43.	The average age of 14 girls and their teacher’s age is 15 years. If the teacher’s age is excluded, the average reduces by 1. What is the teacher's age1). 35 years2). 32 years3). 30 years4). 29 years
Answer» OPTION 4 : 29 YEARS is CORRECT

Discussion

44.	The average of the three numbers x, y and z is 45. x is greater than the average of y and z by 9. The average of y and z is greater than y by 2. Then the difference of x and z is1). 32). 53). 74). 11
Answer» ACCORDING to the question, $ \RIGHTARROW \frac{{x + y + Z}}{3} = 45 $ $ \Rightarrow x + y + z = 135.....(i) $ $ \Rightarrow x = \frac{{y + z}}{2} + 9 $ $ \Rightarrow 2x - y - z = 18.....(ii) $ $ x + y + z = 135 $ $ \underline {2x - y - z = 18} $ $ 3x = 153 $ $ x = 51 $ From (i) $y + z = 135 - 51 = 84.....(iii)$ Also, $ \Rightarrow \frac{{y + z}}{2} = y + 2 $ $ \Rightarrow y + z = 2y + 4 $ $ \Rightarrow z - y = 4 $ $ + y + z = 84 $ $ \underline { - y + z = 4} $ $ \,\,\,\,\,\,\,\,\,2Z = 88 $ $ \,\,\,\,\,\,\,\,\,\,\,\,z = 44 $ Required difference $= 51 - 44 = 7 $

Discussion

45.	The average of three numbers is 40.The first number is twice the second and the second one is thrice the third number.The difference between the largest and the smallest numbers is1). 302). 363). 464). 60
Answer» it from PREVIOUS YEAR ssc PAPERS, option 4 is the RIGHT answer

Discussion

46.	The average monthly income of A and B is Rs 14000,that of B and C is Rs 15600 and A and C is Rs 14400.The monthly income of C is1). Rs 160002). Rs 150003). Rs 140004). Rs 15500
Answer» ANSWER for this QUESTION is OPTION 1

Discussion

47.	The average salary of all the workers in a workshop is Rs8000. The average salary of 7 technicians is Rs12000 and the average salary of the rest is Rs6000.The total number of workers in the workshop is1). 202). 213). 234). 22
Answer» 21 is the correct answer as per the SSC answer key

Discussion

48.	Of the three numbers,second is twice the first and also thrice the third.If the average of the three numbers is 44,the largest number is:1). 242). 723). 364). 108
Answer» is OPTION 2 is the CORRECT ANSWER am i RIGHT

Discussion

49.	The mean high temperature of the first four days of a week is $25^{0}$c whereas the mean of the last four days is $25.5^{0}$C. If the mean temperature of the whole week is $25.2^{0}$C then the temperature on the 4th day is1). $25.5^{0}$C2). $25^{0}$C3). $25.2^{0}$C4). $25.6^{0}$
Answer» OPTION 4 is the RIGHT ONE

Discussion

50.	The average weight of 15 students in a class increases by 1.5kg when one of the students weighing 40 kg is replaced by a new student. What is the weight (in kg) of the new student 1). 64.5 kg2). 56 kg3). 60 kg4). 62.5 kg
Answer» OPTION 4 is the RIGHT ANSWER

Discussion

Explore topic-wise InterviewSolutions in .

A man bought 13 articles at Rs 70 each. 15 at Rs 60 each and 12 at Rs 65 each. The average price per article is1). Rs60.252). Rs64.753). Rs65.754). Rs62.25

The average age of 45 persons is decreased by $\frac{1}{9}$ year when one of them of 60 years is replaced by a new comer. Then the age of the new comer is :1). 45 years2). 55 years3). 59 years4). 49 years

The average mathematics marks of two Sections A and B of Class IX in the annual examination is 74. The average marks of Section A is 77.5 and that of Section B is 70. The ratio of the number of students of Section A and B is1). 7:82). 7:53). 8:74). 8:5

A student finds the average of 10, 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 is1). 42). 33). 24). 5

If the average of eight consecutive even numbers be 93.then the greatest number among them is1). 1002). 863). 1024). 98

Out of seven given numbers,the average of the first four numbers is 4 and that of the last four numbers is also 4.If the average of all the seven numbers is 3.fourth number is1). 32). 43). 74). 11

The average of six numbers is 20. If one number is removed, the average becomes 15. What is the number removed 1). 52). 353). 1124). 45

The mean of 9 observations is 16. One more observation is included and the new mean becomes 17.The 10th observation is1). 92). 163). 264). 30

What is the average of the first six (positive) odd numbers each of which is divisible by 71). 422). 433). 474). 49

The average of 12 numbers is 15 and the average of the first two is 14.What is the average of the rest1). 152). $15\frac{1}{5}$3). 144). $14\frac{1}{5}$

Three numbers are such that the average of first two numbers is 2,the average of the last two numbers is 3 and the average of the first and the last numbers is 4,then the average of three numbers is equal to1). 22). 3.53). 34). 2.5

If out of 10 selected students for an examination, 3 were of 20 years, age, 4 of 21 and 3 of 22 years, the average age of the group is1). 22 years2). 21 years3). 21.5 years4). 20 years

The average of 10 numbers is calculated as 15. It is discovered later on that while calculating the average one number, namely 36, was wrongly read as 26.The correct average is1). 202). 183). 164). 14

Six friends have an average height of 167 cm .A boy with height 162 cm leaves the group. Find the new average height.1). 168cm2). 166cm3). 169cm4). 167cm

The average age of Ram and two children is 17 years and the average age of Ram's wife and the same children is 16 years. If the age of Ram is 33 years, the age of his wife is (in years):1). 312). 323). 354). 30

From a class of 24 boys, a boy , aged 10 years, leaves the class and in his place a new boy is admitted. As a result, the average age of the class is increased by 2 months. What is the age of the new boy 1). 12 years2). 15 years3). 14 years4). 13 years

a,b,c,d,e,f,g are consecutive even numbers.J,k,l,m,n are consecutive odd numbers.The average of all the numbers is1). $3(\frac{a+n}{2})$2). $\frac{l+d}{2}$3). $\frac{a+b+m+n}{4}$4). $\frac{j+c+n+g}{4}$

There were 35 students in a hostel. If the number of students is increased by 7 the expenditure on food increases by Rs.42 per day while the average expenditure of students is reduced by Rs.1. What was the initial expenditure on food per day 1). 4002). 4323). 4424). 420

The average income of 40 persons is Rs 4200 and that of another 35 persons is Rs 4000. The average income of the whole group is:1). Rs 41002). Rs $4106\frac{1}{3}$3). Rs $4106\frac{2}{3}$4). Rs $4108\frac{1}{3}$

A student finds the average of ten 2-digit numbers. While copying numbers, by mistake, he writes one number with its digits interchanged. As a result his answer is 1.8 less than the correct answer.The difference of the digits of the number,in which he made mistake,is1). 22). 33). 44). 6

The average age of four brothers is 12 years. If the age of their mother is also included, the average is increased by 5 years. The age of the mother (in years)is :1). 37 years2). 43 years3). 48 years4). 53 years

Find the average of 1.11, 0.01,0.101, 0.001, 0.111). 0.26642). 0.25543). 0.12644). 0.1164

The average of 6 observations is 45.5. If one new observation is added to the previous observations,then the new average becomes 47.The new observation is1). 582). 563). 504). 46

The average of marks obtained by 120 candidates in a certain examination is 35.If the average marks obtained by passed candidates are 39 and those of the failed candidates are 15. what is the number of candidates who passed the examination 1). 1002). 1203). 1504). 140

The average of marks scored by the students of a class is 68. The average of marks of the girls in the class is 80 and that of boys is 60. What is the percentage of boys in the class 1). 40 %2). 60 %3). 65 %4). 70 %

The average of 30 results is 20 and the average of other 20 results is 30. What is the average of all the results 1). 242). 483). 254). 50

The average age of P, Q and R is 5 years more than R's age. If the total ages of P and Q together is 39 years, then R's age is1). 12 years2). 24 years3). 16 years4). 14 years

The average of 9 integers is found to be 11. But after the calculation,it was detected that, by mistake,the integer 23 was copied as 32. while calculating the average. After the due correction is made, the new average will be1). 102). 93). 10.14). 9.5

The average of marks in Mathematics for 5 students was found to be 50. Later,it was discovered that in the case of one student the marks 48 were misread as 84.The correct average is :1). 40.22). 40.83). 42.84). 48.2

Average of n numbers is a .The first number is increased by 2,second one is increased by 4,the third one is increased by 8 and so on. The average of the new numbers is1). $a+\frac{2^{n-1} -1}{n}$2). $a+2\frac{2^{n}-1}{n}$3). $a+\frac{2^{n-1}}{n}$4). $a+\frac{2^{n}-1}{n}$

The average of 30 numbers is 40 and that of other 40 numbers is 30. The average of all the numbers is1). $34\frac{2}{7}$2). 353). 344). 34.5

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 is1). 42). 53). 144). 20

4 boys and 3 girls spent Rs120 on the average, of which boys spent Rs150 on the average. Then the average amount spent by the girls is1). Rs802). Rs603). Rs904). Rs100

The average age of a cricket team of 11 players is the same as it was 3 years back because 3 of the players whose current average age of 33 years were replaced by 3 youngsters. The average age of the newcomers is1). 23 years2). 21 years3). 22 years4). 20 years

If average of 20 observations $x_{1}$,$x_{2}$.......$x_{20}$ is y ,then the average of $x_{1}- 101$, $x_{2}- 101$,$x_{3}- 101$, .....,$x_{20}- 101$ is1). y-202). y-1013). 20y4). 101y

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 is1). 17 years 1 month2). 17 years 7 month3). 17 years 11 month4). 18 years 3 month

If the average marks of three batches of 55, 60 and 45 students respectively is 50,55 and 60,then the average marks of all the students is1). 54.682). 53.333). 554). None of these

The average age of eleven cricket players is 20 years. If the age of the coach is also included, the average age increases by 10%. The age of the coach is1). 48 years2). 44 years3). 40 years4). 36 years

Of the three numbers,the first number is twice of the second and the second is thrice of the third number.If the average of these 3 numbers is 20,then the sum of the largest and smallest numbers is1). 242). 423). 544). 60

The average age of a husband and his wife was 23 years at the time of their marriage. After five years they have a one year old child .The average age of the family now is1). 29.3 years2). 19 years3). 23 years4). 28.5 years

The average age of 14 girls and their teacher’s age is 15 years. If the teacher’s age is excluded, the average reduces by 1. What is the teacher's age1). 35 years2). 32 years3). 30 years4). 29 years

The average of the three numbers x, y and z is 45. x is greater than the average of y and z by 9. The average of y and z is greater than y by 2. Then the difference of x and z is1). 32). 53). 74). 11

The average of three numbers is 40.The first number is twice the second and the second one is thrice the third number.The difference between the largest and the smallest numbers is1). 302). 363). 464). 60

The average monthly income of A and B is Rs 14000,that of B and C is Rs 15600 and A and C is Rs 14400.The monthly income of C is1). Rs 160002). Rs 150003). Rs 140004). Rs 15500

The average salary of all the workers in a workshop is Rs8000. The average salary of 7 technicians is Rs12000 and the average salary of the rest is Rs6000.The total number of workers in the workshop is1). 202). 213). 234). 22

Of the three numbers,second is twice the first and also thrice the third.If the average of the three numbers is 44,the largest number is:1). 242). 723). 364). 108

The mean high temperature of the first four days of a week is $25^{0}$c whereas the mean of the last four days is $25.5^{0}$C. If the mean temperature of the whole week is $25.2^{0}$C then the temperature on the 4th day is1). $25.5^{0}$C2). $25^{0}$C3). $25.2^{0}$C4). $25.6^{0}$

The average weight of 15 students in a class increases by 1.5kg when one of the students weighing 40 kg is replaced by a new student. What is the weight (in kg) of the new student 1). 64.5 kg2). 56 kg3). 60 kg4). 62.5 kg