Question -
| Marks | 0-10 | 10-20 | 20-30 | 30-40 | 40-50 |
| No. of students | 5 | 8 | 15 | 16 | 6 |
Answer -
To find the mean deviation from the median, firstly let uscalculate the median.
N = 50
So, N/2 = 50/2 = 25
The cumulative frequency just greater than 25 is 58, and thecorresponding value of x is 28
So, Median = 28
By using the formula to calculate Mean,
= 1350/50
= 27
| Class Interval | xi | fi | Cumulative Frequency | |di| = |xi – Median| | fi |di| | FiXi | |Xi – Mean| | Fi |Xi – Mean| |
| 0-10 | 5 | 5 | 5 | 23 | 115 | 25 | 22 | 110 |
| 10-20 | 15 | 8 | 13 | 13 | 104 | 120 | 12 | 96 |
| 20-30 | 25 | 15 | 28 | 3 | 45 | 375 | 2 | 30 |
| 30-40 | 35 | 16 | 44 | 7 | 112 | 560 | 8 | 128 |
| 40-50 | 45 | 6 | 50 | 17 | 102 | 270 | 18 | 108 |
| | N = 50 | | | Total = 478 | Total = 1350 | | Total = 472 |
Mean deviation from Median = 478/50 = 9.56
And, Mean deviation from Median = 472/50 = 9.44
∴ TheMean Deviation from the median is 9.56 and from mean is 9.44.