Frequency distribution table: | Class Interval | Frequency | Cumulative Frequency (Less than type) | |----------------|-----------|----------------------------------------| | 0–10 | 4 | 4 | | 10–20 | 7 | 11 | | 20–30 | 10 | 21 | | 30–40 | 15 | 36 | | 40–50 | 10 | 46 | | 50–60 | 8 | 54 | | 60–70 | 5 | 59 | Here, \(n = 59\), so \(\frac{n}{2} = \frac{59}{2} = 29.5\) The cumulative frequency just greater than 29.5 lies in the class interval (30–40) So, the median class is (30–40) ∴ Median is given by: \[ l + \left[\frac{\frac{n}{2} - cf}{f}\right] \times h \] Where: \(l = 30\), \(n = 59\), \(cf = 21\), \(f = 15\), \(h = 10\) \[ = 30 + \left[\frac{29.5 - 21}{15}\right] \times 10 = 30 + \frac{8.5}{15} \times 10 = 30 + \frac{85}{15} = 30 + 5.67 = 35.67 \quad \text{(approx)} \]