The profit earned when a painting is sold for ₹1,200 is 15 times the loss incurred when it is sold for ₹240. At what price should the painting be sold to make a profit of 40%?

₹420

Let   the cost price of the painting =  x

The profit earned when a painting is sold for 1,200 is 15 times the loss incurred when it is sold for 240.

1200 - x = 15 (x - 240)

1200 - x = 15x - 3600

15x + x = 3600 + 1200

16x = 4800

x= 300

To obtain a profit of 40%, selling price = 300 of (100+40)%

= 300 of 140% = 4200