The following table gives the distribution of daily pocket money (in ₹) received by 30 students:
Class interval (₹): 10–15 15–20 20–25 25–30 30–35
Frequency: 4 6 12 y 5
The mode of the distribution is ₹22. Find the missing frequency y.
(a) 9
(b) 6
(c) 3
(d) 8