हिंदी

If x¯ is the mean of n values of x, then ∑i=1n(xi-x¯) is always equal to ______. If a has any value other than x¯, then ∑i=1n(xi-x¯)2 is ______ than ∑(xi-a)2 - Mathematics

Advertisements
Advertisements

प्रश्न

If `barx` is the mean of n values of x, then `sum_(i = 1)^n (x_i - barx)` is always equal to ______. If a has any value other than `barx`, then `sum_(i = 1)^n (x_i - barx)^2` is ______ than `sum(x_i - a)^2`

रिक्त स्थान भरें

उत्तर

If `barx` is the mean of n values of x, then `sum_(i = 1)^n (x_i - barx)` is always equal to 0. If a has any value other than `barx`, then `sum_(i = 1)^n (x_i - barx)^2` is less than `sum(x_i - a)^2`

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 15: Statistics - Exercise [पृष्ठ २८३]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
अध्याय 15 Statistics
Exercise | Q 41 | पृष्ठ २८३

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Find the mean deviation about the median for the data.

13, 17, 16, 14, 11, 13, 10, 16, 11, 18, 12, 17


Find the mean deviation about the median for the data.

xi 5 7 9 10 12 15
fi 8 6 2 2 2 6

Find the mean deviation about the mean for the data.

Height in cms Number of boys
95 - 105 9
105 - 115 13
115 - 125 26
125 - 135 30
135 - 145 12
145 - 155 10

The lengths (in cm) of 10 rods in a shop are given below:
40.0, 52.3, 55.2, 72.9, 52.8, 79.0, 32.5, 15.2, 27.9, 30.2
 Find mean deviation from median


The lengths (in cm) of 10 rods in a shop are given below:
40.0, 52.3, 55.2, 72.9, 52.8, 79.0, 32.5, 15.2, 27.9, 30.2 

Find mean deviation from the mean also.

 

 


In 34, 66, 30, 38, 44, 50, 40, 60, 42, 51 find the number of observations lying between

\[\bar{ X } \]  − M.D. and

\[\bar{ X } \]  + M.D, where M.D. is the mean deviation from the mean.


In 38, 70, 48, 34, 63, 42, 55, 44, 53, 47 find the number of observations lying between

\[\bar { X } \]  − M.D. and

\[\bar { X } \]   + M.D, where M.D. is the mean deviation from the mean.


Find the mean deviation from the mean for the data:

xi 5 10 15 20 25
fi 7 4 6 3 5

Compute the mean deviation from the median of the following distribution:

Class 0-10 10-20 20-30 30-40 40-50
Frequency 5 10 20 5 10

Find the mean deviation from the mean for the data:

Classes 95-105 105-115 115-125 125-135 135-145 145-155
Frequencies 9 13 16 26 30 12

 


Calculate mean deviation about median age for the age distribution of 100 persons given below:

Age: 16-20 21-25 26-30 31-35 36-40 41-45 46-50 51-55
Number of persons 5 6 12 14 26 12 16 9

Calculate mean deviation from the median of the following data: 

Class interval: 0–6 6–12 12–18 18–24 24–30
Frequency 4 5 3 6 2

The mean of 5 observations is 4.4 and their variance is 8.24. If three of the observations are 1, 2 and 6, find the other two observations.

 

The mean deviation from the median is


The mean deviation of the series aa + da + 2d, ..., a + 2n from its mean is


Let \[x_1 , x_2 , . . . , x_n\]  be n observations and  \[X\]  be their arithmetic mean. The standard deviation is given by

 

The mean deviation of the data 2, 9, 9, 3, 6, 9, 4 from the mean is ______.


Find the mean deviation about the mean of the distribution:

Size 20 21 22 23 24
Frequency 6 4 5 1 4

Find the mean deviation about the median of the following distribution:

Marks obtained 10 11 12 14 15
No. of students 2 3 8 3 4

Mean and standard deviation of 100 items are 50 and 4, respectively. Find the sum of all the item and the sum of the squares of the items.


Determine mean and standard deviation of first n terms of an A.P. whose first term is a and common difference is d.


While calculating the mean and variance of 10 readings, a student wrongly used the reading 52 for the correct reading 25. He obtained the mean and variance as 45 and 16 respectively. Find the correct mean and the variance.


The mean deviation of the data 3, 10, 10, 4, 7, 10, 5 from the mean is ______.


When tested, the lives (in hours) of 5 bulbs were noted as follows: 1357, 1090, 1666, 1494, 1623 
The mean deviations (in hours) from their mean is ______.


The mean of 100 observations is 50 and their standard deviation is 5. The sum of all squares of all the observations is ______.


The sum of squares of the deviations of the values of the variable is ______ when taken about their arithmetic mean.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×