Assume there are four families in a country. The average per capita income of these families is Rs 5000. If the income of three families is Rs 4000, Rs 7000 and Rs 3000 respectively, what is the income of the fourth family?
(i) Rs 7500
(ii) Rs 3000
(iii) Rs 2000
(iv) Rs 6000
(i) Rs 7500
(ii) Rs 3000
(iii) Rs 2000
(iv) Rs 6000