The table given below shows the weights (in kg) of 50 persons:
Weight (in kg) | 42 | 47 | 52 | 57 | 62 | 67 | 72 |
Number of persons | 3 | 8 | 6 | 8 | 11 | 5 | 9 |
Find the mean, median and mode.
Draw the table as below,
Weight in kg (x) | No. of person (f) | Cumulative frequency | Fx |
42 | 3 | 3 | 126 |
47 | 8 | 11 | 376 |
52 | 6 | 17 | 312 |
57 | 8 | 25 | 456 |
62 | 11 | 36 | 682 |
67 | 5 | 41 | 335 |
72 | 9 | 50 | 648 |
N = 50 | ∑fx = 2935 |
We have;
N = 50 (even number)
Median =
Now,
∑fx = 2935 and ∑f = N = 50
Mean =
Hence,
Mode = 3(median) – 2 (mean)
= 3×59.7 - 2×58.7
= 179.1 – 117.4
= 61.1 kg