00:01
Here in this problem we have to find the main deviation about median by using the given data.
00:07
So here in this table we have given the marks, number of girls that is fi, and the mid value of this class interval that is xi.
00:18
Now in order to find the main deviation about median, first of all we will find the median.
00:24
For that we have to find cumulative frequency.
00:27
So here we have 6, 6 plus 8 is 14, 14 plus 14 is 28, 28 plus 16 is 44, 44 plus 4 is 48 and 48 plus 2 is 50 and the summation of fi is 50.
00:55
So here we have n upon 2 is equals to 50 upon 2 which is equals to 25.
01:04
Therefore the median class is 20 to 30 so we have median is equal to 20 plus 25 minus 14 upon 14 into 10 by simplifying it we get median is equals to 20 plus 7 .86 which is equal to 27 .86.
01:40
Now in order to find the mean deviation about median we will find the absolute deviation from the median.
01:53
Since we are finding the absolute deviation so we will ignore the negative sign.
01:57
So here we have 5 minus 27 .86 is 22 .86 15 minus 27 .86 is 12 .86.
02:10
25 minus 27 .86 is 12 .86.
02:14
25 minus 27 .86 is 2 .86...