Weekly income of two persons are in the ratio of 7 : 3 and their weekly expenses are in the ratio of 5 : 2. If each of them saves ₹ 300 per week, then the weekly income of the first person is?

Let the income of two persons are 7k and 3k
Expenditure of first person = 7k - 300
Expenditure of second person = 3k - 300
According to the question,
(7k - 300)/(3k - 300) = 5/2
⇒ 14k - 600 = 15k - 1500
∴ k = 900
Income of first person = 7k = 7 x 900
= ₹ 6300