The ages of 70 members of a choir are shown in inclusive classes. Find the median age.

Step 1. The median class. $\dfrac{N}{2} = 35$. The running totals are $8, 23, 47, \dots$, so the median class is $41$ to $50$, with boundaries $40.5$ and $50.5$.

Step 2. The values. $l = 40.5$, $cf = 23$, $f = 24$ and $h = 10$.

Step 3. The median. $\text{median} = 40.5 + \dfrac{35 - 23}{24} \times 10 = 40.5 + 5 = 45.5$ years.