# RRB NTPC - Averages (200 Questions with Explanation): Quantitative Aptitude Test

21.

In the first 10 overs of a cricket game, the run rate was only 8.2. What should be the run rate in the remaining 40 overs to reach the target of 106 runs?

A.) 0.66
B.) 0.6
C.) 0.82
D.) 0.54

Required Run rate = ( 106 - ( 8.2 x 10 ) )/ (40) = ( 24) /(40) = 0.6

22.

Find the average of the first 56 natural numbers

A.) 28.5
B.) 28
C.) 27.5
D.) 29

Solution is
Average of the first n natural numbers = (n + 1) / 2
Average of the first 56 natural numbers = (56 + 1) / 2
= 57 / 2
= 28.5

23.

The average of 12 numbers is 24. If each number be multiplied by 6. Find the average of new set of numbers?

A.) 48
B.) 144
C.) 65
D.) 121

New Average = Old Average x 6 = 24 x 6 = 144

24.

In a class, the average age of 30 boys is 13 years and the average of 20 girls is 12 years. what is the average age of the whole class?

A.) 12.5 Yrs
B.) 14.2 Yrs
C.) 12.3 Yrs
D.) 12.6 Yrs

Total age of 50 students
(30X 13+20 X 12) = 630
Average =  630/50 = 12.6 Years

25.

Total Marks obtained by a class is 748 and the average score of the class is 68. Find the Total students in the class?

A.) 9
B.) 10
C.) 11
D.) 12

Use the below formula to find the Total, when Average and Total No. of Students is provided Total no of students = Total Marks / Average Marks Total No. of students = ( 748 / 68) = 11

26.

In the first 25 overs of a cricket game, the run rate was only 5.6. What should be the run rate in the remaining 25 overs to reach the target of 280 runs. ?

A.) 6.2
B.) 6.7
C.) 5
D.) 5.6

Required Run rate = ( 280 - ( 5.6 x 25 ) )/ (25) = ( 140) /(25) = 5.6

27.

Physics Teacher knows the average score of 59 students in her subject is 49.5. Can you help the physics teacher to find the overall marks obtained by all the students in her subject?

A.) 2774.48
B.) 2920.5
C.) 3212.55
D.) 3066.53

Use the below formula to find the Total, when Average and Total No. of Students is provided Total = Average * Total Students/People Total = Average * Total Number of Students) Average Weight = ( 49.5 x 59) = 2920.5

28.

Find the average of first 26 multiples of 11

A.) 148.5
B.) 148
C.) 149
D.) 149.5

Solution is:
Average of first 26 natural numbers = ( n + 1 ) / 2
= ( 26 + 1 ) / 2
= 27 / 5
= 13.5
Average of first 26 multiples of 11 = ( Average of first 26 natural numbers ) × 11
= 13.5 × 11
148.5

29.

A man covered a certain distance at a speed of 8 Kmph and returned at a speed of 4 Kmph. Find the average speed of whole journey?

A.) 3 ¾ Kmph
B.) 5 1/3 Kmph
C.) 4 ¼ Kmph
D.) 2 ¼ Kmph

5 1/3 Kmph

30.

There were 22 students in a particular Class. The class teacher knows the overall height of all the students in the class is 1200. Can you find the average height of students in the class?

A.) 54.55
B.) 57.28
C.) 60.01
D.) 51.82

Use the below formula to find the average height of students in the class Average Height = ( Total Height of all students in the Class / Total Number of Students) Average Height = ( 1200/22) = 54.55

31.

In the first 10 overs of a cricket game, the run rate was only 1.8. What should be the run rate in the remaining 20 overs to reach the target of 225 runs?

A.) 10.35
B.) 11.35
C.) 10
D.) 12.35

Required Run rate = ( 225 - ( 1.8 x 10 ) )/ (20) = (207 ) /(20) = 10.35

32.

In the first 10 overs of a cricket game, the run rate was only 7.6. What should be the run rate in the remaining 40 overs to reach the target of 212 runs?

A.) 3.8
B.) 3.4
C.) 4.8
D.) 7.4

Given
First 10 overs in a cricket game
Run rate = 7.6
Required run rate in the remaining 40 overs to reach the target of 212 runs
Required Run rate
= ( 212 - ( 7.6 x 10 ) ) / (40)
= ( 136) / (40)
= 3.4.

33.

Total Marks obtained by a class is 1152 and the average score of the class is 72. Find the Total students in the class?

A.) 17
B.) 15
C.) 16
D.) 14

Use the below formula to find the Total, when Average and Total No. of Students is provided
Total no. of students = Total Marks / Average Marks
Total No. of students = (1152 / 72) = 16

34.

The average of marks of a student of 8 exams was 35. How many marks must be get in the next exam so as to increase his average of marks by 5?

A.) 75
B.) 80
C.) 83
D.) 79

80

35.

Average of five consecutive even numbers is 35. Find the greatest number in these five numbers?

A.) 31
B.) 33
C.) 39
D.) 36

39

36.

The average age of a group of 10 students was 24. The average age increased by 1 years when two new students joined the group. What is the average age of the two new students who joined the group?

A.) 30
B.) 15.5
C.) 19
D.) 19.5

The average age of a group of 10 students is 24
Therefore, the sum of the ages of all 10 of them
= 10 × 24
= 240
When two students joins the group, the average increase by 1
New Average = 25
Now there are 12 students.
Therefore, sum of all the ages of 12 students
= 12 × 25
300
Therefore, the sum of the ages of two students who joined
= 300 - 240
= 60
And the average age of these two students
= 60 / 2
30.

37.

The average age of a group of 10 students was 22. The average age increased by 1 years when two new students joined the group. What is the average age of the two new students who joined the group?

A.) 27
B.) 27.5
C.) 28
D.) 28.5

The average age of a group of 10 students is 22.
Therefore, the sum of the ages of all 10 of them = 10 * 22 = 220
When two students joins the group, the average increase by 1. New Average = 23
Now there are 12 students
Therefore, sum of all the ages of 12 students = 12 X 23 = 276
Therefore, the sum of the ages of two students who joined = 276 - 220 = 56
And the average age of these two students = 28

38.

In a hostel of 12 boys and some girls, an average consumption of rice per month is 12 kg, while the Average consumption for boys is 16 kg per head and for girls 8 kg per head. The number of girls in The hostel?

A.) 11
B.) 12
C.) 12
D.) 13

Number of girls --- G
12+G) × 12 = (12 × 16)+(8 × G)
144 + 12G = 192 + 8G
12G − 8G = 192 − 144
4G = 48
G = 12.

39.

In a class of 31, the overall weight of the students is 997. Can you find the average weight of students in the class?

A.) 35.38
B.) 32.16
C.) 33.77
D.) 30.55

Use the below formula to find the average weight of the class.
Average Weight = ( Total Weight of Class / Total Number of Students)
Average Weight = ( 997/31) = 32.16

40.

In the first 30 overs of a cricket game, the run rate was only 5.4. What should be the run rate in the remaining 20 overs to reach the target of 314 runs?

A.) 8.6
B.) 7.6
C.) 9.6
D.) 9.12