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NDA Statistics PYQs with Solutions

236 previous year questions from Statistics (NDA Mathematics) with answers and solutions. Numbered list, year tags, and one-tap solutions — built for serious JEE / NEET practice.

236 questionsMathematics2011–2026Answers + solutions

About Statistics PYQs

Statistics has 236 previous year questions in the Quantrex Academy NDA Mathematics bank. The 220 questions in this list come from NDA (220), spanning 2011 to 2026. Each question opens on its own page with the options, the correct answer and the worked solution where available.

Questions by year (this list)

  • 2026: 6
  • 2025: 12
  • 2024: 7
  • 2023: 13
  • 2022: 15
  • 2021: 20
  • 2020: 10
  • 2019: 13
  • 2018: 18
  • 2017: 19
  • 2016: 13
  • 2015: 9

Statistics questions with solutions

1

Let two lines of regression be x+y+11=0 and 2x+3y+4=0 for some data. What is the value of correlation coefficient between x and y ?

NDA 2026 Solution View → 2

Passage: The frequency distribution of marks obtained by 100 students in a certain subject is given below : Marks 0 - 10 10 - 20 20 - 30 30 - 40 No. of students 10 20 f 40

NDA 2026 Solution View → 3

The standard deviation of 100 observations is 10 . If 5 is multiplied to each of the observations, then what is the new standard deviation ?

NDA 2026 Solution View → 4

Passage: The frequency distribution of marks obtained by 100 students in a certain subject is given below : Marks 0 - 10 10 - 20 20 - 30 30 - 40 No. of students 10 20 f 40

NDA 2026 Solution View → 5

If the mean of 20 observations, namely x_1,x_2,x_3,…,x_ 20 is 1·414 , then what is the value of ∑_ i=1 ^ 20 100(2x_i+4) ?

NDA 2026 Solution View → 6

If the random variable X has mean 3 and standard deviation 5 , then what is the variance of the random variable Y=2X-5 ?

NDA 2026 Solution View → 7

The standard deviation of 100 observations is 10. If 20 is added to each observation, then what will be the new standard deviation?

NDA 2025 Solution View → 8

Consider the following statements: I. Mean and variance have the same unit of measurement. II. Mean deviation and standard deviation have the same unit of measurement. Which of

NDA 2025 Solution View → 9

Consider the following for the four (04) items that follow: The frequency distribution of height of students of a class is given below: Height (in cm) Number of Students 160–162

NDA 2025 Solution View → 10

Consider the following for the four (04) items that follow: The frequency distribution of height of students of a class is given below: Height (in cm) Number of Students 160–162

NDA 2025 Solution View → 11

Consider the following for the two (02) items that follow: The sum and the sum of squares of the observations corresponding to length X (in cm) and weight Y (in gm) of 50 tropical

NDA 2025 Solution View → 12

The arithmetic mean of 100 observations is 50. If 5 is subtracted from each observation and then divided by 20, then what is the new arithmetic mean?

NDA 2025 Solution View → 13

The standard deviation of 100 observations is 10. If 5 is added to each observation and then divided by 20, then what will be the new standard deviation?

NDA 2025 Solution View → 14

Consider the following for the two (02) items that follow: The sum and the sum of squares of the observations corresponding to length X (in cm) and weight Y (in gm) of 50 tropical

NDA 2025 Solution View → 15

Consider the following for the four (04) items that follow: The frequency distribution of height of students of a class is given below: Height (in cm) Number of Students 160–162

NDA 2025 Solution View → 16

The frequency distribution of the marks obtained by students in a Science examination is given below: Marks 5–15 15–25 25–35 35–45 Number of students 20 30 30 20 What is the

NDA 2025 Solution View → 17

What is the arithmetic mean of 8^2 , 9^2 , 10^2 , … , 15^2 ?

NDA 2025 Solution View → 18

Consider the following for the four (04) items that follow: The frequency distribution of height of students of a class is given below: Height (in cm) Number of Students 160–162

NDA 2025 Solution View → 19

What is the mean deviation of the first 10 natural numbers?

NDA 2024 Solution View → 20

Let ∑_ i=1 ^9 x_i^2=855 . If M is the mean and σ is the standard deviation of x_1, x_2, ….. x_9 , then what is the value of M^2+σ^2 ?

NDA 2024 Solution View → 21

The mean of the series x_1, x_2, …, x_n is x . If x_n is replaced by k , then what is the new mean?

NDA 2024 Solution View → 22

From data (-4,1),(-1,2),(2,7) and (3,1) , the regression line of y on x is obtained as y=a+b x , then what is the value of 2 a+15 b ?

NDA 2024 Solution View → 23

The marks obtained by 10 students in a Statistics test are 24,47,18,32,19,15,21,35,50 and 41. What is the variance of the largest five observations?

NDA 2024 Solution View → 24

x_i 1 2 3 … n f_i 1 2^ -1 2^ -2 … 2^ -(n-1) What is the mean of the distribution?

NDA 2024 Solution View → 25

The marks obtained by 10 students in a Statistics test are 24,47,18,32,19,15,21,35,50 and 41. What is the mean deviation of the largest five observations?

NDA 2024 Solution View → 26

The sum of deviations of n numbers from 10 and 20 are p and q respectively. If (p-q)^2=10000 , then what is the value of n ?

NDA 2023 Solution View → 27

If X =20 is the mean of 10 observations x_1, x_2 …, x_ 10 , then what is the value of ∑_ i=1 ^ 10 ((3 x_i-4)/(5))?

NDA 2023 Solution View → 28

If the mean and the sum of squares of 10 observations are 40 and 16160 respectively, then what is the standard deviation?

NDA 2023 Solution View → 29

If r is the coefficient of correlation between x and y , then what is the correlation coefficient between (3 x+4) and (-3 y+3) ?

NDA 2023 Solution View → 30

The mean and variance of five observations are 14 and 13.2 respectively. Three of the five observations are 11,16 and 20. What are the other two observations?

NDA 2023 Solution View → 31

The central angles p, q, r and s (in degrees) of four sectors in a Pie Chart satisfy the relation 9 p=3 q=2 r=6 s . What is the value of 4 p-q ?

NDA 2023 Solution View → 32

The observations 4,1,4,3,6,2,1,3,4,5,1,6 are outputs of 12 dices thrown simultaneously. If m and M are means of lowest 8 observations and highest 4 observations respectively, then

NDA 2023 Solution View → 33

The bivariate data set contains only two points (-1,1) and (3,2) What will be the line of regression of y on x ?

NDA 2023 Solution View → 34

A die is thrown 10 times and obtained the following outputs: 1,2,1,1,2,1,4,6,5,4 What will be the mode of data so obtained?

NDA 2023 Solution View → 35

Consider the following frequency distribution: What is the value of median of the distribution?

NDA 2023 Solution View → 36

Let P, Q, R represent mean, median and mode. If for some distribution 5 P=4 Q=(R)/(2) , then what is (P+Q)/(2 P+0.7 R) equal to?

NDA 2023 Solution View → 37

For data -1,1,4,3,8,12,17,19,9,11 ; if M is the median of first 5 observations and N is the median of last five observations then what is the value of 4 M-N ?

NDA 2023 Solution View → 38

Let P be the median, Q be the mean and R be the mode of observations x_1, x_2, x_3, … x n . Let S=∑_ i=1 ^n(2 x_i-a)^2. S takes minimum value, when a is equal to

NDA 2023 Solution View → 39

The mean and standard deviation (SD) of marks obtained by 50 students of a class in 4 subjects are given below: Subject Mathematics Physics Chemistry Biology Mean Marks 40 28 38

NDA 2022 Solution View → 40

The coefficient of correlation between ages of husband and wife at the time of marriage for a given set of 100 couples was noted to be 0 · 7 . Assume that all these couples

NDA 2022 Solution View → 41

Consider the following grouped frequency distribution : Class 0-10 10-20 20-30 30-40 40-50 50-60 Frequency 1 2 4 6 4 3 What is mean deviation about the median?

NDA 2022 Solution View → 42

Consider the following grouped frequency distribution : Class 0-10 10-20 20-30 30-40 40-50 50-60 Frequency 1 2 4 6 4 3 What is the median of the distribution?

NDA 2022 Solution View → 43

The frequency curve (assuming unimodal) corresponding to the data obtained in an experiment is skewed to the left. What conclusion can be drawn from the curve?

NDA 2022 Solution View → 44

Consider the following grouped frequency distribution : Class 0-10 10-20 20-30 30-40 40-50 50-60 Frequency 1 2 4 6 4 3 What is the mean deviation about the mean?

NDA 2022 Solution View → 45

The algebraic sum of the deviations of a set of values x_1 , x_2, x_3, … x_n measured from 100 is -20 and the algebriac sum of the deviations of the same set of values measured

NDA 2022 Solution View → 46

The variance of five positive observations is 3.6. If four of the observations are 2,2,4,5 then what is the remaining observation?

NDA 2022 Solution View → 47

Class 0-20 20-40 40-60 60-80 80-100 Frequency 17 p+q 32 p-3 q 19 The total frequency is 120 . The mean is 50 . What is the value of q ?

NDA 2022 Solution View → 48

The algebraic sum of the deviations of a set of values x_1 , x_2, x_3, … x_n measured from 100 is -20 and the algebriac sum of the deviations of the same set of values measured

NDA 2022 Solution View → 49

Class 0-20 20-40 40-60 60-80 80-100 Frequency 17 p+q 32 p-3 q 19 The total frequency is 120. The mean is 50. If the frequency of each class is doubled, then what would be the mean?

NDA 2022 Solution View → 50

The mean and standard deviation (SD) of marks obtained by 50 students of a class in 4 subjects are given below: Subject Mathematics Physics Chemistry Biology Mean Marks 40 28 38

NDA 2022 Solution View → 51

What is the coefficient of mean deviation of 21,34,23,39 , 26,37,40,20,33,27 (taken from mean)?

NDA 2022 Solution View → 52

The algebraic sum of the deviations of a set of values x_1 , x_2, x_3, … x_n measured from 100 is -20 and the algebriac sum of the deviations of the same set of values measured

NDA 2022 Solution View → 53

Class 0-20 20-40 40-60 60-80 80-100 Frequency 17 p+q 32 p-3 q 19 The total frequency is 120 . The mean is 50 . What is the value of p ?

NDA 2022 Solution View → 54

Two regression lines are given as 3 x-4 y+8=0 and 4 x-3 y-1=0 . Consider the following statements : 1. The coefficient of correlations r is (3)/(4) . 2. The means of x and y are 3

NDA 2021 Solution View → 55

The marks obtained by 60 students in a certain subject out of 75 are given below : Marks Number of Students 15-20 4 20-25 5 25-30 11 30-35 6 35-40 5 40-45 8 45-50 9 50-55 6 55-60

NDA 2021 Solution View → 56

For the set of numbers x, x, x+2, x+3, x+10 where x is a natural number, which of the following is/are correct? 1. Mean > Mode 2. Median > Mean Select the correct answer using the

NDA 2021 Solution View → 57

The marks obtained by 60 students in a certain subject out of 75 are given below : Marks Number of Students 15-20 4 20-25 5 25-30 11 30-35 6 35-40 5 40-45 8 45-50 9 50-55 6 55-60

NDA 2021 Solution View → 58

The mean of 10 observations is 5.5. If each observation is multiplied by 4 and subtracted from 44 , then what is the new mean?

NDA 2021 Solution View → 59

Consider the following measures of central tendency for a set of N numbers : 1. Arithmetic mean 2. Geometric mean Which of the above uses/use all the data?

NDA 2021 Solution View → 60

For a histogram based on a frequency distribution with unequal class intervals, the frequency of a class should be proportional to

NDA 2021 Solution View → 61

What is the mean deviation of first 10 even natural numbers?

NDA 2021 Solution View → 62

The coefficient of correlation is independent of

NDA 2021 Solution View → 63

The numbers of Science, Arts and Commerce graduates working in a company are 30,70 and 50 respectively. If these figures are represented by a pie chart, then what is the angle

NDA 2021 Solution View → 64

The following table gives the frequency distribution of number of peas per pea pod of 198 pods : What is the median of this distribution?

NDA 2021 Solution View → 65

If M is the mean of n observations x_1-k, x_2-k, x_3-k , …, x_n-k , where k is any real number, then what is the mean of x_1, x_2, x_3, …, x_n ?

NDA 2021 Solution View → 66

For which of the following sets of numbers do the mean, median and mode have the same value?

NDA 2021 Solution View → 67

If the mean of a frequency distribution is 100 and the coefficient of variation is 45 \% , then what is the value of the variance?

NDA 2021 Solution View → 68

What is the sum of deviations of the variate values 73 , 85,92,105,120 from their mean?

NDA 2021 Solution View → 69

If ∑_ i=1 ^ 10 x_i=110 and ∑_ i=1 ^ 10 x_i^2=1540 then what is the variance?

NDA 2021 Solution View → 70

When the measure of central tendency is available in the form of mean, which one of the following is the most reliable and accurate measure of variability?

NDA 2021 Solution View → 71

The mean of 12 observations is 75. If two observations are discarded, then the mean of the remaining observations is 65. What is the mean of the discarded observations?

NDA 2021 Solution View → 72

If the mode of the scores 10,12,13,15,15,13,12,10, x is 15 , then what is the value of x ?

NDA 2021 Solution View → 73

The average of a set of 15 observations is recorded, but later it is found that for one observation, the digit in the tens place was wrongly recorded as 8 instead of 3. After

NDA 2021 Solution View → 74

Paragraph: Read the following information and answer: Consider the following statements : 1. Modal value of the marks in Physics lies in the interval 30-40 . 2. Median of the

NDA 2020 Solution View → 75

Paragraph: Read the following information and answer: What is the mean of marks in Physics?

NDA 2020 Solution View → 76

The arithmetic mean of 100 observations is 40. Later, it was found that an observation '53' was wrongly read as ' 83 '. What is the correct arithmetic mean?

NDA 2020 Solution View → 77

A data set of n observations has mean 2 M , while another data set of 2 n observations has mean M . What is the mean of the combined data sets?

NDA 2020 Solution View → 78

The sum of deviations of n number of observations measured from 2.5 is 50. The sum of deviations of the same set of observations measured from 3.5 is -50. What is the value of n ?

NDA 2020 Solution View → 79

Paragraph: Read the following information and answer: The difference between number of students under Physics and Mathematics is largest for the interval

NDA 2020 Solution View → 80

The numbers 4 and 9 have frequencies x and (x-1) respectively. If their arithmetic mean is 6 , then what is the value of x ?

NDA 2020 Solution View → 81

If Σ x_i=20, Σ x_i^2=200 and n=10 for an observed variable x , then what is the coefficient of variation?

NDA 2020 Solution View → 82

Let X and Y represent prices (in ₹) of a commodity in Kolkata and Mumbai respectively. It is given that X=65, Y=67 , σ_X=2.5, σ_Y=3.5 and r(X, Y)=0.8 . What is the equation of

NDA 2020 Solution View → 83

What is the standard deviation of the observations - 6 ,- 5 ,- 4 ,-1,1, 4 , 5 , 6 ?

NDA 2020 Solution View → 84

The median of the observations 22,24,33,37, x+1, x+3,46 , 47,57,58 in ascending order is 42. What are the values of 5 th and 6 th observations respectively?

NDA 2019 Solution View → 85

Arithmetic mean of 10 observations is 60 and sum of squares of deviations from 50 is 5000. What is the standard deviation of the observations?

NDA 2019 Solution View → 86

For the variables x and y , the two regression lines are 6 x+y=30 and 3 x+2 y=25 . What are the values of x , y and r respectively?

NDA 2019 Solution View → 87

The class marks in a frequency table are given to be 5,10 , 15,20,25,30,35,40,45,50 . The class limits of the first five classes are

NDA 2019 Solution View → 88

The mean of 5 observations is 4.4 and variance is 8.24. If three of the five observations are 1,2 and 6, then what are the other two observations?

NDA 2019 Solution View → 89

Consider the following discrete frequency distribution: array lcccccccc x & 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 f & 3 & 15 & 45 & 57 & 50 & 36 & 25 & 9 array What is the value of median

NDA 2019 Solution View → 90

Mean of 100 observations is 50 and standard deviation is 10. If 5 is added to each observation, then what will be the new mean and new standard deviation respectively?

NDA 2019 Solution View → 91

If V is the variance and M is the mean of first 15 natural numbers, then what is V+M^2 equal to?

NDA 2019 Solution View → 92

The mean of 100 observations is 50 and the standard deviation is 10. If 5 is subtracted from each observation and then it is divided by 4 , then what will be the new mean and the

NDA 2019 Solution View → 93

Let the correlation coefficient between X and Y be 0.6. Random variables Z and W are defined as Z=X+5 and W=(Y)/(3) . What is the correlation coefficient between Z and W ?

NDA 2019 Solution View → 94

If all the natural numbers between 1 and 20 are multiplied by 3 , then what is the variance of the resulting series ?

NDA 2019 Solution View → 95

If the range of a set of observations on a variable X is known to be 25 and if Y=40+3 X , then what is the range of the set of corresponding observations on Y?

NDA 2019 Solution View → 96

Consider the following statements: 1. The algebraic sum of deviations of a set of values from their arithmetic mean is always zero. 2. Arithmetic mean > Median > Mode for a

NDA 2019 Solution View → 97

Consider the following statements: 1. If 10 is added to each entry on a list then the average increase by 10. 2. If 10 is added to each entry on a list, then the standard

NDA 2018 Solution View → 98

If the regression coefficient of Y on X is -6 , and the correlation coefficient between X and Y is -(1)/(2) , then the regression coefficient of X on Y would be

NDA 2018 Solution View → 99

The set of bivariate observation (x_1, y_1), (x_ 2 , y_ 2 ), … . . (x_ n , y_ n ) are such that all the values are distinct and all the observations fall on a straight line with

NDA 2018 Solution View → 100

In any discrete series (when all values are not same) if x represents mean deviation about mean and y represents standard deviation, then which one of the following is correct?

NDA 2018 Solution View → 101

An analysis of monthly wages paid to the workers in two firms A and B belonging to the same industry the following result: The average of monthly wages and variance of

NDA 2018 Solution View → 102

The variance of 25 observations is 4. If 2 is added to each observation, then the new variance of the resulting observations is

NDA 2018 Solution View → 103

In which one of the following cases would you except to get a negative correlation?

NDA 2018 Solution View → 104

The correlation coefficient computed from a set of 30 observations is 0.8. Then the percentage of variation not explained by linear regression is

NDA 2018 Solution View → 105

If the correlation coefficient between x and y is 0.6 , covariance is 27 and variance of y is 25 , then what is the variance of x ?

NDA 2018 Solution View → 106

Let x be the mean of x_1, x_2, x_3, …, x_n . If x_i=a+cy_i for some constants a and c , then what will be the mean of y_1, y_2, y_3, …., y_ n ?

NDA 2018 Solution View → 107

Consider the following statements: 1. If the correlation coefficient r_ x y =0 , then the two lines of regression are parallel to each other. 2. If the correlation coefficient r_

NDA 2018 Solution View → 108

Consider the following statements: 1. Mean is independent of change in scale and change in origin. 2. Variance is independent of change in scale but not in origin. Which of the

NDA 2018 Solution View → 109

In a test in Mathematics, 20 \% of the students obtained "first class". If the data are represented by a Pie-Chart, what is the central angle corresponding to "first class"?

NDA 2018 Solution View → 110

Consider the following statements: 1. The sum of deviations from mean is always zero. 2. The sum of absolute deviations is minimum when taken around median. Which of the above

NDA 2018 Solution View → 111

The standard deviation σ of the first N natural numbers can be obtained using which one of the following formulae?

NDA 2018 Solution View → 112

What is the median of the numbers 4.6,0,9.3,-4.8,7.6,2.3, 12.7,3.5, 8.2,6.1,3.9, 5.2?

NDA 2018 Solution View → 113

Which one of the following can be obtained from an ogive?

NDA 2018 Solution View → 114

The mean and standard deviation of a set of values are 5 and 2 respectively. If 5 is added to each value, then what is the coefficient of variation for the new set of values?

NDA 2018 Solution View → 115

Given that the arithmetic mean and standard deviation of a sample of 15 observations are 24 and 0 respectively. Then which one of the following is the arithmetic mean of the

NDA 2017 Solution View → 116

Consider the following statements : 1. Variance is unaffected by change of origin and change of scale. 2. Coefficient of variance is independent of the unit of observations. Which

NDA 2017 Solution View → 117

The following table gives the monthly expenditure of two families: In constructing a pie diagram to the above data, the radii of the circles are to be chosen by which one of the

NDA 2017 Solution View → 118

The coefficient of correlation when coefficients of regression are 0.2 and 1.8 is

NDA 2017 Solution View → 119

The variance of 20 observations is 5. If each observation is multiplied by 3 , then what is the new variance of the resulting observations?

NDA 2017 Solution View → 120

The mean of a group of 100 observations was found to be 20. Later it was found that four observations were incorrect, which were recorded as 21,21,18 and 20. What is the mean if

NDA 2017 Solution View → 121

If two regression lines between height ( x ) and weight ( y ) are 4 y-15 x+410=0 and 30 x-2 y-825=0 , then what will be the correlation coefficient between height and weight?

NDA 2017 Solution View → 122

The mean weight of 150 students in a certain class is 60 kg. The mean weight of boys in the class is 70 kg and that of girls is 55 kg. What is the number of boys in the class?

NDA 2017 Solution View → 123

If the data are moderately non-symmetrical, then which one of the following empirical relationships is correct?

NDA 2017 Solution View → 124

In an examination, 40 \% of candidates got second class. When the data are represented by a pie chart, what is the angle corresponding to second class?

NDA 2017 Solution View → 125

Consider the following statements : Statement 1: Range is not a good measure of dispersion. Statement 2 : Range is highly affected by the existence of extreme values. Which one of

NDA 2017 Solution View → 126

Data can be represented in which of the following forms? 1. Textual form 2. Tabular form 3. Graphical form Select the correct answer using the code given below.

NDA 2017 Solution View → 127

If the regression coefficient of x on y and y on x are -(1)/(2) and -(1)/(8) respectively, then what is the correlation coefficient between x and y ?

NDA 2017 Solution View → 128

Consider the following statements : 1. Coefficient of variation depends on the unit of measurement of the variable. 2. Range is a measure of dispersion. 3. Mean deviation is least

NDA 2017 Solution View → 129

Which one of the following can be considered as appropriate pair of values of regression coefficient of y on x and regression coefficient of x on y ?

NDA 2017 Solution View → 130

It is given that X =10, Y =90, σ_X=3, σ_Y=12 and r_ XY =0.8 . The regression equation of X on Y is

NDA 2017 Solution View → 131

If a variable takes values 0,1,2,3, …, n with frequencies 1, C(n, 1), C(n, 2), C(n, 3), …., C(n, n) respectively, then the arithmetic mean is

NDA 2017 Solution View → 132

For given statistical data, the graphs for less than ogive and more than ogive are drawn. If the point at which the two curves intersect is P , then abscissa of point P gives the

NDA 2017 Solution View → 133

A sample of 5 observations has mean 32 and median 33. Later it is found that an observation was recorded incorrectly as 40 instead of 35. If we correct the data, then which one of

NDA 2017 Solution View → 134

The scores of 15 students in an examination were recorded as 10,5,8,16,18,20,8,10,16,20,18,11,16,14 and 12. After calculating the mean, median and mode, an error is found. One of

NDA 2016 Solution View → 135

For 10 observations on price ( x ) and supply (y), the following data was obtained: aligned & ∑ x=130, ∑ y=220 & ∑ x^2=2288, ∑ y^2=5506 and ∑ xy=3467 . aligned What is line of

NDA 2016 Solution View → 136

In a study of two groups, the following results were obtained: Which of the following statements is correct?

NDA 2016 Solution View → 137

Consider the following statements in respect of class intervals of grouped frequency distribution: 1. Class intervals need not be mutually exclusive. 2. Class intervals should be

NDA 2016 Solution View → 138

Two variates, x and y , are uncorrelated and have standard deviations σ_x and σ_y respectively. What is the correlation coefficient between x+y and x-y ?

NDA 2016 Solution View → 139

A random sample of 20 people is classified in the following table according to their ages: What is the mean age of this group of people?

NDA 2016 Solution View → 140

If the covariance between x and y is 30 , variance of x is 25 and variance of y is 144 , then what is the correlation coefficient?

NDA 2016 Solution View → 141

What is the mean deviation from the mean of the numbers 10,9,21,16,24 ?

NDA 2016 Solution View → 142

For the data 3,5,1,6,5,9,5,2,8,6 the mean, median and mode are x, y and z respectively. Which one of the following is correct?

NDA 2016 Solution View → 143

If the total number of observations is 20, Σ x_ i =1000 and Σ x_ i^2=84000 , then what is the variance of the distribution?

NDA 2016 Solution View → 144

Consider the following statements in respect of a histogram: 1. The total area of the rectangles in a histogram is equal to the total area bounded by the corresponding frequnecy

NDA 2016 Solution View → 145

Consider the following statements: 1. The mean and median are equal in symmetric distribution. 2. The range is the difference between the maximum value and the minimum value in

NDA 2016 Solution View → 146

The mean of the series x_1, x_2, …, x_n is X . If x_2 is replaced by λ , then what is the new mean?

NDA 2016 Solution View → 147

Which one of the following measures of central tendency is used in construction of index numbers?

NDA 2015 Solution View → 148

The regression coefficients of a bivariate distribution are -0.64 and -0.36. Then the correlation coefficient of the distribution is

NDA 2015 Solution View → 149

The geometric mean of the observations x_1, x_2, x_3, … . . x_ n is G_1 , The geometric mean of the observations y_1, y_2, y_3, … y_ n is G_2 . The geometric mean of observations

NDA 2015 Solution View → 150

Which of the following statements is/are correct in respect of regression coefficients? 1. It measures the degree of linear relationship between two variables. 2. It gives the

NDA 2015 Solution View → 151

A set of annual numerical data, comparable over the years, is given for the last 12 years. 1. The data is best represented by a broken line graph, each corner (turning point)

NDA 2015 Solution View → 152

The ‘less than’ ogive curve and the ‘more than’ ogive curve intersect at

NDA 2015 Solution View → 153

The mean and the variance 10 observations are given to be 4 and 2 respectively. If every observation is multiplied by 2 , the mean and the variance of the new series will be

NDA 2015 Solution View → 154

The correlation coefficient between two variables X and Y is found to be 0 · 6 . All the observations on X and Y are transformed using the transformations U=2-3 X and V=4Y+1 . The

NDA 2015 Solution View → 155

The mean of five numbers is 30. If one number is excluded, their mean becomes 28. The excluded number is

NDA 2015 Solution View → 156

Consider the following statements in respect of histogram: 1. The histogram is a suitable representation of a frequency distribution of a continuous variable. 2. The area included

NDA 2014 Solution View → 157

The variance of 20 observations is 5. If each observation is multiplied by 2 , then what is the new variance of the resulting observations?

NDA 2014 Solution View → 158

If x and y are the means of two distributions such that x < y and z is the mean of the combined distribution, then which one of the following statements is correct?

NDA 2014 Solution View → 159

What is the mean deviation about the mean for the data 4,7,8,9,10,12,13,17 ?

NDA 2014 Solution View → 160

For two variables x and y , the two regression coefficients are b_ y x =-3 / 2 and b_ x y =-1 / 6 . The correlation coefficient between x and y is:

NDA 2014 Solution View → 161

The cumulative frequency of the largest observed value must always be:

NDA 2014 Solution View → 162

Paragraph : The number of telephone calls received in 245 successive one minute intervals at an exchange is given below in the following frequency distribution. Number of calls 0

NDA 2014 Solution View → 163

Paragraph : The mean and standard deviation of 100 items are 50, 5 and that of 150 items are 40, 6 respectively. Question : What is the combined mean of all 250 items?

NDA 2014 Solution View → 164

Paragraph : The mean and standard deviation of 100 items are 50, 5 and that of 150 items are 40, 6 respectively. Question : What is the combined standard deviation of all 250

NDA 2014 Solution View → 165

Paragraph : The mean and standard deviation of 100 items are 50, 5 and that of 150 items are 40, 6 respectively. Question : What is the variance of all the 250 items?

NDA 2014 Solution View → 166

Paragraph : The number of telephone calls received in 245 successive one minute intervals at an exchange is given below in the following frequency distribution. Number of calls 0

NDA 2014 Solution View → 167

The regression lines will be perpendicular to each other if the coefficient of correlation r is equal to

NDA 2014 Solution View → 168

The variance of numbers x_1, x_2, x_3, … x_n is V. Consider the following statements: 1. If every x_i is increased by 2 , the variance of the new set of numbers is V. 2. If the

NDA 2014 Solution View → 169

p, q, r, s, t are five numbers such that the average of p , q and r is 5 and that of s and t is 10. What is the average of all the five numbers?

NDA 2014 Solution View → 170

Paragraph : The number of telephone calls received in 245 successive one minute intervals at an exchange is given below in the following frequency distribution. Number of calls 0

NDA 2014 Solution View → 171

The mean of 20 observations is 15. On checking, it was found that two observation were wrongly copied as 3 and 6. If wrong observations are replaced by correct values 8 and 4

NDA 2013 Solution View → 172

Coefficient of correlation is the measure of

NDA 2013 Solution View → 173

Consider the following statements: 1. Both the regression coefficients have same sign. 2. If one of the regression coefficients is greater than unity, the other must be less than

NDA 2013 Solution View → 174

Consider the following statements: 1. The algebraic sum of the deviations of a set of n values from its arithmetic mean is zero. 2. In the case of frequency distribution, mode is

NDA 2013 Solution View → 175

Consider the following statements: 1. Pie diagrams are suitable for categorical data. 2. The arc length of a sector of a pie diagram is proportional to the value of the component

NDA 2013 Solution View → 176

The variance of 20 observations is 5. If each observation is multiplied by 2 , then what is the new variance of the resulting observations?

NDA 2013 Solution View → 177

The marks obtained by 13 students in a test are 10,3 , 10,12,9,7,9,6,7,10,8,6,7 . The median of this data is

NDA 2013 Solution View → 178

Consider the following statements: 1. Both variance and standard deviation are measures of variability in the population. 2. Standard deviation is the square of the variance.

NDA 2013 Solution View → 179

What is the variance of the first 11 natural numbers?

NDA 2013 Solution View → 180

The average marks obtained by the students in a class are 43. If the average marks obtained by 25 boys are 40 and the average marks obtained by the girl students are 48 , then

NDA 2013 Solution View → 181

Variance is always independent of the change of

NDA 2013 Solution View → 182

Marks obtained by 7 students in a subject are 30,55 , 75,90,50,60,39 . The number of students securing marks less than the mean marks is

NDA 2013 Solution View → 183

The standard deviation of the observations 5,5,5,5 , 5 is

NDA 2013 Solution View → 184

Which one of the following measures is determined only after the construction of cumulative frequency distribution?

NDA 2013 Solution View → 185

Consider the following frequency distribution: If the total of the frequencies is 100 and mode is 25 , then which one of the following is correct?

NDA 2013 Solution View → 186

If two lines of regression are perpendicular, then the correlation coefficient r is

NDA 2013 Solution View → 187

The mean of 10 observations is 5. If 2 is added to each observation and then multiplied by 3 , then what will be the new mean?

NDA 2012 Solution View → 188

The algebraic sum of the deviations of 20 observations measured from 30 is 2. What would be the mean of the observations?

NDA 2012 Solution View → 189

The arithmetic mean of numbers a, b, c, d, e is M What is the value of (a-M)+(b-M)+(c-M)+(d-M)+(e-M) ?

NDA 2012 Solution View → 190

What is the standard deviation of 7,9,11,13,15 ?

NDA 2012 Solution View → 191

The median of 27 observations of a variable is 18 Three more observations are made and the values of these observations are 16,18 and 50. What is the median of these 30

NDA 2012 Solution View → 192

Which of one of the following is a measure of dispersion?

NDA 2012 Solution View → 193

A variate X takes values 2,9,3,7,5,43,2,10 . What is the median?

NDA 2012 Solution View → 194

Consider the following statements: 1. Two independent variables are always uncorrelated. 2. The coefficient of correlation between two variables X and Y is positive when X

NDA 2012 Solution View → 195

If the mean of few observations is 40 and standard deviation is 8 , then what is the coefficient of variation?

NDA 2012 Solution View → 196

Frequency curve may be :

NDA 2012 Solution View → 197

What is the mode for the data 20,20,20,21,21,21 , 2121,22,22,22,22,22,22,22,23,23,23,23,23,24 , 24,25 ?

NDA 2012 Solution View → 198

Consider the following statements: 1. A continuous variable can take all values in an interval. 2. A random variable which takes a finite number of values is necessarily discrete.

NDA 2012 Solution View → 199

Students of three sections of a class, having 30,30 and 40 students appeared for a test of 100 marks. The arithmetic means of the marks of the three sections are 72.2,69.0 and

NDA 2011 Solution View → 200

The mean of 7 observations is 10 and that of 3 observations is 5. What is the mean of all the 10 observations?

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Related NDA Mathematics chapters

Trigonometric Ratios & Identities (295)Probability (201)Sequences and Series (182)Three Dimensional Geometry (176)Quadratic Equation (157)Matrices (153)Determinants (130)Functions (129)Permutation and Combination (129)Differential Equations (127)Definite Integration (110)Differentiation (104)

Statistics in other exams

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