A man spends 31% and 9% of his monthly income on food and clothing, respectively, and one third of the remaining on the education of children. He saves Rs. 4,500 per month, which is equal to half the balance after spending on food, clothing and education of children. His monthly salary is:
1
Rs. 21,000
2
Rs. 22,500
3
Rs. 20,650
4
Rs. 26,700