The weekly earnings (in ₹) of 45 auto-rickshaw drivers in Ranchi:
500-1000 -> 5, 1000-1500 -> 9, 1500-2000 -> 14, 2000-2500 -> 10, 2500-3000 -> 7.
Find the median weekly earning (₹).

Cumulative: 5, 14, 28, 38, 45, so $n=45$ and $\frac{n}{2}=22.5$. The first cf to reach 22.5 is 28, so the median class is 1500-2000 with $l=1500$, cf = 14, $f=14,h=500$. Median = $1500+\left(\frac{22.5-14}{14}\right)\times 500=1500+303.57=₹1803.57$. Note that cf and $f$ happen to be equal here; that is a coincidence of this table, not a rule. 1821.43 uses $\frac{n+1}{2}=23$ instead of $\frac{n}{2}$. 1303.57 uses cf = 28, the cumulative frequency of the median class itself. 1500.61 omits the factor $h=500$.