Raman and Dhawan invested in a business in the ratio 5: 2. If 9% of the total profit goes to charity. If Dhawan's share is Rs.405.6, then what is the total profit earned?

First remove the 9% charity from total profit, leaving 91% to distribute. Raman and Dhawan split this in 5:2 ratio, so Dhawan receives 2/7 of the distributed amount. Setting 0.91 × total × (2/7) = 405.6 and solving gives total profit = Rs.1560. This matches the selling price structure where profit at higher price equals loss at lower price, making the cost price exactly midway between them.