The average monthly salary of all teaching and non-teaching persons is 4750. The number of teaching persons is 5 less than that of non-teaching persons. The average monthly salary of teaching persons is Rs. 4500 and the average monthly salary of non-teaching persons is Rs. 4950. Find the sum of the number of teaching and non-teaching persons.
1
35
2
70
3
45
4
55
5
65