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1.Find the missing frequency f, if the mode of the given data is 154.
Classes
120-130
130-140
140-150
150-160
160-170
170-180
Frequency
2
8
12
f
9
7
plzz give an answer fast....
how to calculate mode if two classes have same and highest frequency (bimodal) ?
what is hit and trial method .
Mode and mean of a data are 12k and 15k. Median of the data is
If the median of the distribution is given below is 28.5, find the values of x and y.
Class interval
0 − 10
5
10 − 20
x
20 − 30
20
30 − 40
15
40 − 50
y
50 − 60
Total
60
IF THE N/2 IS EQUAL TO THE CUMULATIVE FREQUENCY THEN WE WOULD REGARD THAT CLASS AS THE MEDIAN CLASS OR NOT.
if the median of the following frequency distribution is 24. find the missing frequency x :
Age Number of persons
0 - 10 5
10 - 20 25
20 - 30 x
30 - 40 18
40 - 50 7
find the missing frequencies if N=100 and median is 32.
marks obtained-0-10, 10-20, 20-30, 30-40, 40-50, 50-60, total
no. of students-10 ,? ,25 ,30 ,? ,10 ,100.
di is the deviation of xi from assumed mean a.
If mean = x + ∑fidi/∑fi, then x is
The median of the following distribution is 30. Find the missing frequencies f1 and f2:
Class frequency
0-10 10
10-20 10
20-30 f1
30-40 30
40-50 f2
50-60 10
Total 100
In a school 85 boys and 35 girls appeared in a public examination . The mean marks of the boys were found to be 40 % whereas the mean marks of the girls were 60% . Determine the average marks % of the school.
the mean of 10 numbers is 20.if 5 is subtracted from every number.what will be the new mean?
1. Observe the information's in the following cumilative frequency table
no. of days absent
less than 5
less than 10
less than 15
less than 20
less than 25
less than 30
less than 35
less than 40
less than 45
No. of students
29
224
465
582
634
644
650
653
655
Q.. Draw a 'less than' ogive and 'more than' ogive to represent the above data .
Q... Find median for the above data by interpreting the graph.
Q...why regularity is essential in students life (VBQ)
how to find the mean if the class intervals are unequal??
like fr e- 0-10,10-30,30-35....
The mean of 25 observations is 9 . if each observation is increased by 4 then the new mean is _______
how to find xi?
…………………. Is called a positional average.
What is the formula to use median when more than ogive is given?
In the step deviation method,
What is the meaning of ui ?
find the circumference of a sector of angle 60, of a circle with radius 10cm
A class teacher has the following absentee record of 40 students of a class for the whole term. Find the mean number of days a student was absent.
Number of days
0 − 6
6 − 10
10 − 14
14 − 20
20 − 28
28 − 38
38 − 40
Number of students
11
10
4
3
1
in a grouped frequency distribution,the class with the maximum frequency is called?
a.mean class b.median class c.modal class d.distribution class
3 Median = Mode + 2 Mean
please proof it.
Q1) among the following which is not the measure of central tendency?
A) Mean B) Median C) Mode D) range
Q2) among the following which is the best measure of central tendency?
A) Mean B) Median C) Mode
In a continuous frequency distribution, the median of the data is 21.If each observation is increased by 5 find the new median
The mean and median of same data are 24 and 26 respectively. The value of mode is ?
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
14
6
Convert the distribution above to a less than type cumulative frequency distribution, and draw its ogive.
The following table shows the distribution of some families according to expenditure per week .the number of families for two class intervalsare missing. Median =Rs.25 , Mode = Rs.24. calculate the missing frequency and hence the find mean.
Find the value of f1 from the following data if it's mode is 65:
0-20 6
20-40 8
40-60 f1
60-80 12
80-100 6
100-120 5
Where frequency 6,8, f1, and 12 are in ascending order.
how do we find mean using step deviation method if the classes are unequal?
should we make the classes equal in such a case?
the mean of first n odd natural numbers is n2/81,then n=
the interest paid on each of the three different sums of money yeilding 1%, 2% and 4% simple interest per annum respectively, is the same. find the average yield percent on the total sum inverted.
if the mean of the following frequency distribution is 91, find the missing frequency x and y :
classes frequency
0 - 30 12
30-60 21
60 - 90 x
90 -120 52
120 - 150 y
150 - 180 11
total 150
The median from the table is
value 7, 8, 9, 10, 11, 12 ,13
frequency 2, 1, 4, 5, 6, 1, 3
The mean of n observations is X . IF the first item is increased by 1, second by 2 and so on, then the new mean is:
1. X+n
2. X+n/2
3. X+(n+1)/2
4. X+(n-1)/2
Draw two ogives for the following distribution and also find median.
During the medical check-up of 35 students of a class, their weights were recorded as follows:
Weight (in kg)
Less than 38
0
Less than 40
Less than 42
Less than 44
Less than 46
Less than 48
28
Less than 50
32
Less than 52
35
Draw a less than type ogive for the given data. Hence obtain the median weight from the graph verify the result by using the formula.
the mean height of 29 male worker is 71 cms and 31 female workers is 48 cms. find the combined mean height of all 60 workers in the factory.
Find the sum of deviations of the variate values 3, 4, 6, 7, 8, 14 fromtheir mean.
A set of numbers consists of four 5's, six 7's, ten 9's, eleven 12's, three 13's, two 14's. The mode of this set of numbers is
the median of the data is 525. find x and y, if total frequency is 100
class 0-100 100-200 200-300 300-400 400-500 500-600 600-700 700-800 800-900 900-1000
frequeency 2 5 x 12 17 20 y 9 7 4
In a given data if the MODAL CLASS is at the bottom(last) and has nothing Preceeding it then how will we find the MODE?
9. If the mean of the distribution is 57.6 and the sum of its observations is 50, find the missing
The mean of the following frequency dristibution is 50. Find the value of p
how can we find the median by only less than ogive curve?
the mean age of combined group of men and women is 30 years. if the mean of the age of men and women are respectively 32 and 27, then the percentage of women in the group is ??
The median of the following data is 32.5.find the value of x and y
class interval f
0-10 x
10-20 5
20-30 9
30-40 12
40-50 y
50-603
60-70 2
total 40
The following table shows the marks obtained by 100 students of class X in a school during a particular academic session. Find the mode of this distribution.
Marks No. of students
Less than 10 7
Less than 20 21
Less than 30 34
Less than 40 46
Less than 50 66
Less than 60 77
Less than 70 92
Less than 80 100
Find the mean, mode and median for the following data.
The median of the following data is 20.75. Find the missing frequencies x and y, if the total frequency is 100.
Class interval:-0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40
Frequencies: -7 10 x 13 y 10 14 9
Find the combined mean of the group of 150, if the mean of 50 students 40 and that of other 100 students is 50.
how to find the median class?
what is cumulative frequency????
How to find missing frequency if the mode of the given data is given.
A cricket player played 7 matches and scored 88, 72, 90, 94, 56, 62, and 76 runs. What is the average score or mean score of the player in these 7 matches?
We know that,
“The mean is the sum of all observations divided by the number of observations”.
We can use the following formula to find the mean of the given data.
Using this formula, the mean of scores obtained by the player
= 76.86
Thus, the average score of the player is 76.86. There are many situations where the number of observations is very large and then it is not possible to use this formula to find the mean of the given data.
Let us consider such a situation.
We have the marks distribution of 100 students of a class in a Mathematics test. The distribution is given in the form of groups like 0 − 10, 10 − 20 …. To find the mean in such situations, we follow another method. This method is explained in the given video.
Let us solve some more examples to understand the concept better.
Example 1:
The following table shows the various income brackets of the employees of a company.
25000 −
30000
30000 −
35000
35000 −
40000
40000 −
45000
18
13
Find the average monthly income of each employee.
Solution:
Firstly, we will calculate the class marks of each class interval and then the product of the class marks with the corresponding frequencies. By doing so, we obtain the following table.
Income of employees
(in Rupees)
No. of employees: fi
Class Mark: xi
xi × fi
10000 − 15000
15000 − 20000
20000 − 25000
25000 − 30000
30000 − 35000
35000 − 40000
40000 − 45000
12500
17500
22500
27500
32500
37500
42500
400000
315000
292500
192500
455000
187500
467500
Total (∑)
100
2310000
The mean can now be easily calculated using the formula.
Mean
Hence, the average income of the employees is Rs 23100.
Example 2:
The mean of the following frequency distribution is 62.8 and the sum of all the frequencies is 50. Find the value of f1 and f2.
Class Interval
0 − 20
20 − 40
40 − 60
60 − 80
80 − 100
f1
f2
50
Firstly, let us find the class marks of each class interval and then the product of class marks with the corresponding frequencies for each class interval as shown in the following table.
Frequency: fi
Class Mark: xi
30
70
90
110
30 f1
500
70 f2
630
880
30 + f1 + f2 = 50
2060 + 30 f1 + 70 f2
It is given that the sum of the frequencies is 50.
∴ 30 + f1 + f2 = 50
f1 + f2 = 20
f1 = 20 − f2 … (1)
The mean is given as 62.8.
∴ = 62.8
i cant understand that which me thod should use in different question pls explain
How to convert a LESS THAN OGIVE and it's CF into the Frequency distribution?
The given table lists the frequency distribution of 40 observations.
0 10
11 20
21 30
31 40
41 50
Frequency (fi)
Find the class marks of classes 10 - 25 and 35 - 55.
if the median salary of 100 employees of a factory is 24800, then find the missing frequencies f1
and f2 in the given data
Salary 10000-15000 15000-20000 20000-25000 25000-30000 30000-35000 35000-40000
frequen. 18 f1 f2 15 12 22
If the mean of the following distributions is 27, Find the value of p
If the less than ogive and more than ogive intersect each other at ( 20.5,15.5 ), then the median of the given data is :
A ) 36.0 B) 20.5 C ) 15.5 D ) 5.5
The mean of the following data is 53, find the missing frequencies.
age in years -- 0-20, 20-40 40-60 60-80, 80-100
number of people--- 15, f1, 21, f2, 17, 100
In a given data, if mode is 2.73 more than the mean, then by how much will the median of that data be more or less than the mode of that data?
the class mark of classes in a distribution arer 6.10.14.18.22.26.30. find
a) class size
b) lower limit of second class
c) upper lmit of last class
d) third class
plz answer these question i have got my exams on sunday fast plz :))))))
1.in what time is Rs5600 amount to Rs6720 at 8% per annum?
2.what amount a person will get after 2.5 years at 8% per annum if he invested Rs2650 in the bank?
3.What sum will amount to Rs5525 at 10% per annum simple interest in 3 years?
E.g: 9876543210, 01112345678
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Syllabus
1.Find the missing frequency f, if the mode of the given data is 154.
Classes
120-130
130-140
140-150
150-160
160-170
170-180
Frequency
2
8
12
f
9
7
plzz give an answer fast....
how to calculate mode if two classes have same and highest frequency (bimodal) ?
what is hit and trial method .
Mode and mean of a data are 12k and 15k. Median of the data is
If the median of the distribution is given below is 28.5, find the values of x and y.
Class interval
Frequency
0 − 10
5
10 − 20
x
20 − 30
20
30 − 40
15
40 − 50
y
50 − 60
5
Total
60
IF THE N/2 IS EQUAL TO THE CUMULATIVE FREQUENCY THEN WE WOULD REGARD THAT CLASS AS THE MEDIAN CLASS OR NOT.
if the median of the following frequency distribution is 24. find the missing frequency x :
Age Number of persons
0 - 10 5
10 - 20 25
20 - 30 x
30 - 40 18
40 - 50 7
Height (in cm)
150
155
158
160
164
168
No. of students
10
15
8
14
7
16
Find the mean height.
(Step-deviation method has been deleted for 2021)
[Question from M.L. Aggarwal book]
find the missing frequencies if N=100 and median is 32.
marks obtained-0-10, 10-20, 20-30, 30-40, 40-50, 50-60, total
no. of students-10 ,? ,25 ,30 ,? ,10 ,100.
di is the deviation of xi from assumed mean a.
If mean = x + ∑fidi/∑fi, then x is
The median of the following distribution is 30. Find the missing frequencies f1 and f2:
Class frequency
0-10 10
10-20 10
20-30 f1
30-40 30
40-50 f2
50-60 10
Total 100
In a school 85 boys and 35 girls appeared in a public examination . The mean marks of the boys were found to be 40 % whereas the mean marks of the girls were 60% . Determine the average marks % of the school.
the mean of 10 numbers is 20.if 5 is subtracted from every number.what will be the new mean?
1. Observe the information's in the following cumilative frequency table
no. of days absent
less than 5
less than 10
less than 15
less than 20
less than 25
less than 30
less than 35
less than 40
less than 45
No. of students
29
224
465
582
634
644
650
653
655
Q.. Draw a 'less than' ogive and 'more than' ogive to represent the above data .
Q... Find median for the above data by interpreting the graph.
Q...why regularity is essential in students life (VBQ)
how to find the mean if the class intervals are unequal??
like fr e- 0-10,10-30,30-35....
The mean of 25 observations is 9 . if each observation is increased by 4 then the new mean is _______
A teacher asked the students to collect the marks of the students in maths periodic test out of 50 marks a student collected the marks and prepare the frequency distribution table as per the instructions of the teacher from the frequency table again student prepare less than cf distribution and then he draws less than ogive as shown in above right sided figure construct the frequency distribution table using the less than ogive and then find the median marks
Can you please help me to solve this question. Please don't give similar answer
how to find xi?
…………………. Is called a positional average.
What is the formula to use median when more than ogive is given?
In the step deviation method,
What is the meaning of ui ?
median.
Classes 20-30 30-40 40-50 50-60 60-70 70-80 80-90
frequency 10 8 12 24 6 25 15
find the circumference of a sector of angle 60, of a circle with radius 10cm
A class teacher has the following absentee record of 40 students of a class for the whole term. Find the mean number of days a student was absent.
Number of days
0 − 6
6 − 10
10 − 14
14 − 20
20 − 28
28 − 38
38 − 40
Number of students
11
10
7
4
4
3
1
Height(in cm)
Less than 8
Less than 16
Less than 24
Less than 32
Less than 40
Less than 48
Less than 56
No: of plants
22
43
83
118
176
256
300
Draw a more than ogive for the above data and hence determine the median from it
Marks Below 10 Below 20 Below 30 Below 40 Below 50 Below 60 Below 70 Below 80 Below 90 Below 100
No. of students 5 9 17 29 45 60 70 78 83 85
in a grouped frequency distribution,the class with the maximum frequency is called?
a.mean class b.median class c.modal class d.distribution class
3 Median = Mode + 2 Mean
please proof it.
Q1) among the following which is not the measure of central tendency?
A) Mean B) Median C) Mode D) range
Q2) among the following which is the best measure of central tendency?
A) Mean B) Median C) Mode
In a continuous frequency distribution, the median of the data is 21.If each observation is increased by 5 find the new median
The mean and median of same data are 24 and 26 respectively. The value of mode is ?
marks number of students
0 and above 80
10 and above 77
20 and above 72
30 and above 65
40 and above 55
50 and above 43
60 and above 28
70 and above 16
80 and above 10
90 and above 8
100 and above 0
20-40
40-60
60-80
80-100
17
f1
f2
f3
19
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
Convert the distribution above to a less than type cumulative frequency distribution, and draw its ogive.
The following table shows the distribution of some families according to expenditure per week .the number of families for two class intervalsare missing. Median =Rs.25 , Mode = Rs.24. calculate the missing frequency and hence the find mean.
Find the value of f1 from the following data if it's mode is 65:
Class frequency
0-20 6
20-40 8
40-60 f1
60-80 12
80-100 6
100-120 5
Where frequency 6,8, f1, and 12 are in ascending order.
how do we find mean using step deviation method if the classes are unequal?
should we make the classes equal in such a case?
the mean of first n odd natural numbers is n2/81,then n=
the interest paid on each of the three different sums of money yeilding 1%, 2% and 4% simple interest per annum respectively, is the same. find the average yield percent on the total sum inverted.
if the mean of the following frequency distribution is 91, find the missing frequency x and y :
classes frequency
0 - 30 12
30-60 21
60 - 90 x
90 -120 52
120 - 150 y
150 - 180 11
total 150
The median from the table is
value 7, 8, 9, 10, 11, 12 ,13
frequency 2, 1, 4, 5, 6, 1, 3
The mean of n observations is X . IF the first item is increased by 1, second by 2 and so on, then the new mean is:
1. X+n
2. X+n/2
3. X+(n+1)/2
4. X+(n-1)/2
Draw two ogives for the following distribution and also find median.
class frequency
40-50 5
50-60 x
60-70 15
70-80 2
80-90 7
During the medical check-up of 35 students of a class, their weights were recorded as follows:
Weight (in kg)
Number of students
Less than 38
0
Less than 40
3
Less than 42
5
Less than 44
9
Less than 46
14
Less than 48
28
Less than 50
32
Less than 52
35
Draw a less than type ogive for the given data. Hence obtain the median weight from the graph verify the result by using the formula.
the mean height of 29 male worker is 71 cms and 31 female workers is 48 cms. find the combined mean height of all 60 workers in the factory.
Class interval Frequency
0-10 10
10-20 20
20-30 x
30-40 40
40-50 y
50-60 25
60-70 15
(in percent)
is the ans median class 60-70 and modal class 50-60??
family size:0-4,4-8,8-12,12-16,16-20
number of families:8,14,12,4,2
find median and mode.
Find the sum of deviations of the variate values 3, 4, 6, 7, 8, 14 from
their mean.
A set of numbers consists of four 5's, six 7's, ten 9's, eleven 12's, three 13's, two 14's. The mode of this set of numbers is
Class interval Frequency
10-20 12
20-30 30
30-40 f1
40-50 65
50-60 f2
60-70 25
70-80 18
no links plz.
the median of the data is 525. find x and y, if total frequency is 100
class 0-100 100-200 200-300 300-400 400-500 500-600 600-700 700-800 800-900 900-1000
frequeency 2 5 x 12 17 20 y 9 7 4
In a given data if the MODAL CLASS is at the bottom(last) and has nothing Preceeding it then how will we find the MODE?
9. If the mean of the distribution is 57.6 and the sum of its observations is 50, find the missing
Classes Frequency
0-5 7
5-10 6
10-15 f
15-20 4
20-25 3
a) f <8
b) f >8
c) f > 8 only
d) f<7
The mean of the following frequency dristibution is 50. Find the value of p
how can we find the median by only less than ogive curve?
the mean age of combined group of men and women is 30 years. if the mean of the age of men and women are respectively 32 and 27, then the percentage of women in the group is ??
The median of the following data is 32.5.find the value of x and y
class interval f
0-10 x
10-20 5
20-30 9
30-40 12
40-50 y
50-603
60-70 2
total 40
The following table shows the marks obtained by 100 students of class X in a school during a particular academic session. Find the mode of this distribution.
Marks No. of students
Less than 10 7
Less than 20 21
Less than 30 34
Less than 40 46
Less than 50 66
Less than 60 77
Less than 70 92
Less than 80 100
Class Interval
20-30
30-40
40-50
50-60
60-70
Frequency
25
47
62
p
10
Find the mean, mode and median for the following data.
Marks
obtained
No. 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 median of the following data is 20.75. Find the missing frequencies x and y, if the total frequency is 100.
Class interval:-0-5 5-10 10-15 15-20 20-25 25-30 30-35 35-40
Frequencies: -7 10 x 13 y 10 14 9
Marks
Less than 10
Less than 20
Less than 30
Less than 40
Less than 50
Less than 60
Less than 70
Less than 80
No: of students
7
21
34
46
66
77
92
100
Find the combined mean of the group of 150, if the mean of 50 students 40 and that of other 100 students is 50.
how to find the median class?
what is cumulative frequency????
How to find missing frequency if the mode of the given data is given.
A cricket player played 7 matches and scored 88, 72, 90, 94, 56, 62, and 76 runs. What is the average score or mean score of the player in these 7 matches?
We know that,
“The mean is the sum of all observations divided by the number of observations”.
We can use the following formula to find the mean of the given data.
Using this formula, the mean of scores obtained by the player
Thus, the average score of the player is 76.86. There are many situations where the number of observations is very large and then it is not possible to use this formula to find the mean of the given data.
Let us consider such a situation.
We have the marks distribution of 100 students of a class in a Mathematics test. The distribution is given in the form of groups like 0 − 10, 10 − 20 …. To find the mean in such situations, we follow another method. This method is explained in the given video.
Let us solve some more examples to understand the concept better.
Example 1:
The following table shows the various income brackets of the employees of a company.
Income of employees (in Rupees)10000 − 1500015000 − 2000020000 − 2500025000 −
30000
30000 −
35000
35000 −
40000
40000 −
45000
No. of employees32
18
13
7
14
5
11
Find the average monthly income of each employee.
Solution:
Firstly, we will calculate the class marks of each class interval and then the product of the class marks with the corresponding frequencies. By doing so, we obtain the following table.
Income of employees
(in Rupees)
No. of employees: fi
Class Mark: xi
xi × fi
10000 − 15000
15000 − 20000
20000 − 25000
25000 − 30000
30000 − 35000
35000 − 40000
40000 − 45000
32
18
13
7
14
5
11
12500
17500
22500
27500
32500
37500
42500
400000
315000
292500
192500
455000
187500
467500
Total (∑)
100
2310000
The mean can now be easily calculated using the formula.
Mean![]()
![]()
Hence, the average income of the employees is Rs 23100.
Example 2:
The mean of the following frequency distribution is 62.8 and the sum of all the frequencies is 50. Find the value of f1 and f2.
Class Interval
Frequency
0 − 20
20 − 40
40 − 60
60 − 80
80 − 100
100 − 120
5
f1
10
f2
7
8
Total
50
Solution:
Firstly, let us find the class marks of each class interval and then the product of class marks with the corresponding frequencies for each class interval as shown in the following table.
Class Interval
Frequency: fi
Class Mark: xi
xi × fi
0 − 20
20 − 40
40 − 60
60 − 80
80 − 100
100 − 120
5
f1
10
f2
7
8
10
30
50
70
90
110
50
30 f1
500
70 f2
630
880
30 + f1 + f2 = 50
2060 + 30 f1 + 70 f2
It is given that the sum of the frequencies is 50.
∴ 30 + f1 + f2 = 50
f1 + f2 = 20
f1 = 20 − f2 … (1)
The mean is given as 62.8.
∴![]()
= 62.8
i cant understand that which me thod should use in different question pls explain
How to convert a LESS THAN OGIVE and it's CF into the Frequency distribution?
The given table lists the frequency distribution of 40 observations.
Class interval
0 10
11 20
21 30
31 40
41 50
Frequency (fi)
5
f1
f2
7
11
Find the class marks of classes 10 - 25 and 35 - 55.
if the median salary of 100 employees of a factory is 24800, then find the missing frequencies f1
and f2 in the given data
Salary 10000-15000 15000-20000 20000-25000 25000-30000 30000-35000 35000-40000
frequen. 18 f1 f2 15 12 22
If the mean of the following distributions is 27, Find the value of p
Q). Find the mean, median and mode of the following data:
If the less than ogive and more than ogive intersect each other at ( 20.5,15.5 ), then the median of the given data is :
A ) 36.0 B) 20.5 C ) 15.5 D ) 5.5
The mean of the following data is 53, find the missing frequencies.
age in years -- 0-20, 20-40 40-60 60-80, 80-100
number of people--- 15, f1, 21, f2, 17, 100
Total = 50
height in cm frequency cumulative frequency
150-155 12 a
155-160 b 25
160-165 10 c
165-170 d 43
170-175 e 48
175-180 2 f
In a given data, if mode is 2.73 more than the mean, then by how much will the median of that data be more or less than the mode of that data?
the class mark of classes in a distribution arer 6.10.14.18.22.26.30. find
a) class size
b) lower limit of second class
c) upper lmit of last class
d) third class
plz answer these question i have got my exams on sunday fast plz :))))))
1.in what time is Rs5600 amount to Rs6720 at 8% per annum?
2.what amount a person will get after 2.5 years at 8% per annum if he invested Rs2650 in the bank?
3.What sum will amount to Rs5525 at 10% per annum simple interest in 3 years?