Find the mean deviation about the mean for the given data.
\(x_i\) | 5 | 10 | 15 | 20 | 25 |
\(f_i\) | 7 | 4 | 6 | 3 | 5 |
\(x_i\) | \(f_i\) | \(f_ix_i\) | \(|x_i-\bar{x}|\) | \(f_i|x_i-\bar{x}|\) |
5 | 7 | 35 | 9 | 63 |
10 | 4 | 40 | 4 | 16 |
15 | 6 | 90 | 1 | 6 |
20 | 3 | 60 | 6 | 18 |
25 | 5 | 125 | 11 | 55 |
25 | 350 | 158 |
\(N=\sum_{I=1}^{5}f_i=25\)
\(N=\sum_{I=1}^{5}f_ix_i=350\)
∴ \(\bar{x}=\frac{1}{N}\sum_{I=1}^{5}f_ix_i=\frac{1}{25}×350=14\)
∴ \(=MD\bar{(x)}=\frac{1}{N}\sum_{i=1}^{5}f_i|x_i-\bar{x}|=\frac{1}{25}×158=6.32\)
Class : | 4 – 6 | 7 – 9 | 10 – 12 | 13 – 15 |
Frequency : | 5 | 4 | 9 | 10 |
Marks : | Below 10 | Below 20 | Below 30 | Below 40 | Below 50 |
Number of Students : | 3 | 12 | 27 | 57 | 75 |
\(\text{Length (in mm)}\) | 70-80 | 80-90 | 90-100 | 100-110 | 110-120 | 120-130 | 130-140 |
---|---|---|---|---|---|---|---|
\(\text{Number of leaves}\) | 3 | 5 | 9 | 12 | 5 | 4 | 2 |
What is the Planning Process?
A statistical measure that is used to calculate the average deviation from the mean value of the given data set is called the mean deviation.
The mean deviation for the given data set is calculated as:
Mean Deviation = [Σ |X – µ|]/N
Where,
Grouping of data is very much possible in two ways: