If 30% of A's salary is ₹600 more than 20% of B's salary, and the ratio of their salaries is 4:5, find A's salary.

वेतन 4x, 5x। 0.3(4x) - 0.2(5x) = 600। 1.2x - 1x = 600 => 0.2x = 600 => x = 3000। A का वेतन = 4 * 3000 = ₹12,000।