The following data represent the daily pocket money (in rupees) received by students of a school.
Class interval (₹): 0–10 10–20 20–30 30–40 40–50
Frequency: p 9 q 12 8
The total number of students is 50 and their mean pocket money is ₹ 28. Answer the questions below.
(i) Form two separate equations in p and q using the information about the total number of students and the mean.
(ii) Solve the simultaneous equations obtained in part (i) to find the values of p and q.
(iii) Substitute the values of p and q in the data and verify that the mean pocket money is ₹ 28.