The following table shows the weights of 12 students.
Weight (in kg) | 47 | 50 | 53 | 56 | 60 |
Number of students | 4 | 3 | 2 | 2 | 4 |
Draw the table as below,
Weight in kg (x) | No. of students (f) | Cumulative frequency | Fx |
47 | 4 | 4 | 188 |
50 | 3 | 7 | 150 |
53 | 2 | 9 | 106 |
56 | 2 | 11 | 112 |
60 | 4 | 15 | 240 |
N = 15 | ∑fx = 796 |
We have;
N = 15(0dd number)
Median = value of the term
= value of 8th term
= 53
Now,
∑fx = 796 and ∑f = N = 15
Mean =
Hence,
Mode = 3(median) – 2 (mean)
= 3×53 - 2×53.06
= 159 – 106.12
= 52.88
So, Mean, median and mode are 53, 53.06 and 52.88