Find the mean of the following data.
The mean of the following data is 14. Find the value of k.
If the mean of the following distribution is 54, then find the value of p.
Find the mean of the following frequency distribution using assumed mean method.
Find the mean of the following data, by using step deviation method.
In a health check up, the number of heart beats of 40 women were recorded in the following table:
Number of heart 65-69 70-74 75-79 80-84
beats/minute
Number of women 2 18 16 4
Find the mean of the data.
In a class test, marks obtained by 120 students are given in the following frequency distribution. If it is given that mean is 59, then find the missing frequencies x and y.
Mark Number
0-10 1
10-20 3
20-30 7
30-40 10
40-50 15
50-60 x
60-70 9
70-80 27
80-90 18
90-100 y
An NGO working for welfare of cancer patients, maintained its records as follows:
Age of patient (in year) 0-20 20-40 40-60 60-80
Number of patients 35 315 120 50
Find mode.
If mode of the following series is 54, then find the value of f.
Class interval 0-15 15-30 30-45 45-60 60-75 75-90
Frequency 3 5 f 16 12 7
Find the modal class in which the given mode lies and find the value of f by using the formula,
Find the median of the first ten prime numbers.
The set of data given below shows the ages of participants in a certain summer camp. Draw a cumulative frequency table for the data.
Age (in year) 10 11 12 13 14 15
Frequency 3 18 13 12 7 27
Consider a grouped frequency distribution of marks obtained, out of 100, by 58 students, in a certain examination, as follows:
Marks Number of students
0-10 5
10-20 7
20-30 4
30-40 2
40-50 3
50-60 6
60-70 7
70-80 9
80-90 8
90-100 7
From the cumulative frequency distribution of less than type and more than type.
The following distribution gives cumulative frequencies of 'more than type':
Marks obtained 5 10 15 20
(more than or equal to)
Number of students 30 23 8 2
(cumulative frequency)
Change the above data into a continuous grouped frequency distribution.
The following distribution gives the daily income of 50 workers of a factory:
Daily income (in Rs) 100-120 120-140 140-160 160-180 180-200
Number of workers 12 14 8 6 10
Write the above distribution as 'less than type' cumulative frequency distribution.
Find the median of the following data.
Marks obtained 20 29 28 42 19 35 51
Number of students 3 4 5 7 9 2 3
Obtain the median for the following frequency distribution.
x 1 2 3 4 5 6 7 8 9
y 8 10 11 16 20 25 15 9 6
200 surnames were randomly picked up from a local telephone directory and the frequency distribution of the number of letters in English alphabets in the surnames was obtained as follows:
Number of letters 0-5 5-10 10-15 15-20 20-25
Number of surnames 20 60 80 32 8
Find the median of the above data.
A survey regarding the heights (in cm) of 51 boys of class X of a school was conducted and the following data was obtained:
Height (in cm) Number of boys
Less than 140 4
Less than 145 11
Less than 150 29
Less than 155 40
Less than 160 46
Less than 165 51
Find the median height.
Find the missing frequencies in the following frequency distribution table, if n = 100 and median is 32.
Marks obtained 0-10 10-20 20-30 30-40 40-50 50-60 Total
Number of students 10 ? 25 30 ? 10 100
If median = 137 units and mean = 137.05 units, then find the mode.
From the following frequency distribution, prepare the "less then" ogive.
Rainfall (in cm) 5-15 15-25 25-35 35-45 45-55 55-65
Number of days 22 10 8 15 5 6
Draw a 'more than type' ogive from the following distribution.
Marks obtained 10-19 20-29 30-39 40-49 50-59
Number of candidates 6 7 5 10 3
Draw a 'less than type' ogive for the following frequency distribution.
Marks 0-10 10-20 20-30 30-40 40-50 50-60
Number of students 5 8 6 10 6 6
Find the median from the graph and also verify the result.
The following table gives the height of trees:
Height (Less than) 7 14 21 28 35 42 49 56
Number of trees 26 57 92 134 216 287 341 360
Draw 'less than ogive' and 'more than ogive'. Also, find the median.
A survey was conducted by a group of students as a part of their environment awareness programme, in which they collected the following data regrading the number of plants in 20 houses in a locality. Find the mean number of plants per house. How environment awareness programme for students makes environment healthy.
Number of plants 0-2 2-4 4-6 6-8 8-10 10-12 12-14
Number of houses 1 2 1 5 6 2 3
Which method will you use for finding the mean and why?
The following distribution shows the daily pocket allowance of children of a locality. The mean pocket allowance is Rs 18. Find the missing frequency f.
Daily pocket allowance (in Rs) Number of children
11-13 7
13-15 6
15-17 9
17-19 13
19-21 f
21-23 5
23-25 4
To find out the concentration of in the air (in parts per million, i.e. ppm), the data was collected for 30 localities in a certain city and is presented below:
Concentration of Frequency
(in ppm)
0.00 - 0.04 4
0.04 - 0.08 9
0.08 - 0.12 9
0.12 - 0.16 2
0.16 - 0.20 4
0.20 - 0.24 2
Find the mean concentration of in the air.
The following table shows the ages of the patients admitted in a hospital during a year:
Age (in year) 5-15 15-25 25-35 35-45 45-55 55-65
Number of patients 6 11 21 23 14 5
Find the mode and the mean of the data given above. Compare and interpret the two measures of central tendency.
A student noted the number of cars passing through a spot on a road for 100 periods each of 3 min and summarised it in the table given below:
Number of cars 0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80
Frequency 7 14 13 12 20 11 15 8
Find the mode of the data.
The following frequency distribution gives the monthly consumption of electricity of 68 monthly consumers of a locality. Find (i) median, (ii) mean and (iii) mode of the data and compare them. (iv) How electricity consumption can be reduced?
Monthly consumption (in units) Number of consumers
65-85 4
85-105 5
105-125 13
125-145 20
145-165 14
165-185 8
185-205 4
The length of 40 leaves of a plant are measured correct to the nearest millimetre and the data obtained is represented in the following table:
Length (in mm) Number of leaves
118-126 3
127-135 5
136-144 9
145-153 12
154-162 5
163-171 4
172-180 2
Find the median length of leaves.
If and , find the value of .
If the mean of the following distribution is 6, find the value of .
2 4 6 10 a+5
3 2 3 1 2
In the following distribution, find the number of families having income range 16000-19000 (in Rs).
Monthly income range (in Rs) Number of families
Income more than Rs 10000 100
Income more than Rs 13000 85
Income more than Rs 16000 69
Income more than Rs 19000 50
Income more than Rs 22000 33
Income more than Rs 25000 15
In an arranged series of 4n terms, which term is median?
For the following distribution find the modal class.
If are the mid-points of the class intervals of grouped data, are corresponding frequencies and is the mean, find the value of .
The time (in seconds) taken by 150 athletes to run a 110 m hurdle race are tabulated below:
Class interval Frequency
13.8-14.0 2
14.0-14.2 4
14.2-14.4 5
14.4-14.6 71
14.6-14.8 48
14.8-15.0 20
Find the number of athletes, who completed the race in less than 14.6 s.
Consider the following data:
Class interval 65-85 85-105 105-125 125-145 145-165 165-185 185-205
Frequency 4 5 13 20 14 7 4
Find the difference of the upper limit of the median class and the lower limit of the modal class.
Find the value of k for the following distribution whose mean is 16.6.
8 12 15 k 20 25 30
12 16 20 24 16 8 4
The following table gives the number of pages written by Sarika for completing her own book for 30 days:
Number of pages 16-18 19-21 22-24 25-27 28-30
written per day
Number of days 1 3 4 9 13
Find the mean number of pages written per day.
Construct the frequency distribution table for the given data.
Marks Number of students
Less than 10 14
Less than 20 22
Less than 30 37
Less than 40 58
Less than 50 67
Less than 60 75
The daily income of a sample of 50 employees are tabulated as follows:
Income (in Rs) 1-200 201-400 401-600 601-800
Number of employees 14 15 14 7
Find the mean daily income of employees.
Find the value of k, if the mean of the following distribution is 20.
x 15 17 19 20 + k 23
f 2 3 4 5k 6
Find the unknown entries m, n, o, p, q and r in the following distribution of heights of students in a class and the total number of students is 50.
Height (in cm) 150-155 155-160 160-165 165-170 170-175 175-180
Frequency 12 n 10 p q 2
Cumulative m 25 o 43 48 r
frequency
An incomplete distribution is given as follows:
Class interval Frequency
0-10 10
10-20 20
20-30 ?
30-40 40
40-50 ?
50-60 25
60-70 15
The median value is 35 and the sum of all the frequencies is 170. Using the median formula, fill up the missing frequencies.
For the following distribution, calculate mean by using direct method.
Class interval 1-4 4-9 9-16 16-27
Frequency 6 12 26 20
Determine the mean of the following distribution
Marks Number of students
Below 10 5
Below 20 9
Below 30 17
Below 40 29
Below 50 45
Below 60 60
Below 70 70
Below 80 78
Below 90 83
Below 100 85
The length of 40 leaves of a plant are measured correct upto the nearest millimetre and the data is as under.
Length (in mm) Number of leaves
118-126 4
126-134 5
134-142 10
142-150 12
150-158 4
158-166 5
Find the mean and median length of the leaves.
Draw 'more than ogive' for the frequency distribution and hence obtain the median.
Class interval 5-10 10-15 15-20 20-25 25-30 30-35 35-40
Frequency 2 12 2 4 3 4 3
Following is the cumulative frequency distribution (of less than type) of 1000 persons each of age 20 yr and above. Determine the mean age.
Age (in years) Below 30 Below 40 Below 50 Below 60 Below 70 Below 80
Number of persons 100 220 350 750 950 1000
The mean of the following frequency distribution is 62.8 and the sum of all the frequencies is 50. Compute the missing frequencies .
Class interval 0-20 20-40 40-60 60-80 80-100 100-120
Frequency 5 10 7 8
Find the missing frequencies and the median the following distribution, if the mean is 1.46
Number of accidents 0 1 2 3 4 5 Total
Number of days (frequency) 46 ? ? 25 10 5 200
Find the missing frequencies and the median for the following distribution, if the mean is 1.46
Number of accidents 0 1 2 3 4 5 Total
Number of days (frequency) 46 ? ? 25 10 5 200
Following data was obtained regarding concentration of sulphur dioxide in the air (in parts per million, i.e. ppm) in 24 for a awareness programme related to environment localities of a city:
Concentration of (in ppm) Frequency
0.00-0.02 2
0.02-0.04 5
0.04-0.06 4
0.06-0.08 3
0.08-0.10 4
0.10-0.12 6
Find the mean and median concentration of in the air. what value is indicated from this action?
A health officer took an initiative of organising a medical camp in a remote village. The medical checkup of 35 students of the age group of 10 yr and their weights were recorded as follows:
weight (in kg) Number of students
38-40 3
40-42 2
42-44 4
44-46 5
46-48 14
48-50 4
50-52 3
(i) Find the mean weight of students using step deviation method.
(ii) Which value of health officer was depicted in this situation?
In the following frequency distribution table, find the missing values.
Class interval 0-8 8-16 16-24 24-32 32-40 40-48
Frequency 15 18 9
Cumulative frequency 15 28 43 61 80
If the mean of the following distribution is 2.6, then find the value of y.
Variable 1 2 3 4 5
Frequency 4 5 y 1 2
Calculate mode of the following data.
Marks obtained 0-20 20-40 40-60 60-80 80-100
Number of students 8 10 12 6 3
Write the empirical relationship between the three measures of central tendency.
Find the mode of the data, using an empirical formula, when it is given that median = 41.25 and mean = 33.75.
The abscissa of the point of intersection of the less than type and more than type cumulative frequency curves of a grouped data gives which measure of central tendency?
In a class test, 50 students obtained marks as follows.
Marks obtained 0-20 20-40 40-60 60-80 80-100
Number of students 4 6 25 10 5
Find the modal class and the median class.
If mode = 80 and mean = 110, then find the median.
If , then find the value of .
If the mean of the following data is 18.75, then find the value of p.
10 15 p 25 30
5 10 7 8 2
Find p, if the mean of the given data is 15.75.
Class interval 0-6 6-12 12-18 18-24 24-30
Frequency 6 8 p 9 7
Find the mode of the given data.
Class interval 3-6 6-9 9-12 12-15 15-18 18-21 21-24
Frequency 2 5 10 23 21 12 3
The weight (in kg) of 50 wrestlers are recorded in the following table:
Weight (in kg) 100-110 110-120 120-130 130-140 140-150
Number of wrestlers 4 14 21 8 3
Find the mean weight of the wrestlers.
Karan scored 36 marks in English, 44 marks in Hindi, 75 marks in Mathematics and x marks in Science. If he has scored an average of 50 marks, then find the value of x.
The ages of employees in a factory are as follows:
Age (in years) 17-23 23-29 29-35 35-41 41-47 47-53
Number of employees 2 5 6 4 2 1
Find the median age of the employees.
In the following data, find the values of p and q. Also, find the median class and modal class.
Class interval 100-200 200-300 300-400 400-500 500-600 600-700
Frequency 11 12 10 q 20 14
Cumulative frequency 11 p 33 46 66 80
Find the mode of the following distribution.
Class interval 0-20 20-40 40-60 60-80 80-100
Frequency 25 16 28 20 5
Compute the median for the following data.
Class interval (less than) 20 30 40 50 60 70 80 90 100
Cumulative frequency 0 4 16 30 46 66 82 92 100
Find the mean of the following data and hence find the mode, given that median of the data is 42.5.
Class interval 10-20 20-30 30-40 40-50 50-60 60-70 70-80
Frequency 4 8 10 12 10 4 2
Using step deviation method, find the mean of the following data.
Class interval Frequency
135-140 4
140-145 9
145-150 18
150-155 28
155-160 25
160-165 10
165-170 5
170-175 2
An aircraft has 120 passenger seats. The number of seats occupied during 100 flights is given in the following table:
Number of seats 100-104 104-108 108-112 112-116 116-120
Frequency 15 20 32 18 15
Determine the mean number of seats occupied over the flights.
The mean of the following distribution is 132 and sum of frequencies is 50. Find the values of x and y.
Class interval 0-40 40-80 80-120 120-160 160-200 200-240
Frequency 4 7 x 12 y 9