profit and loss

Two third of a consignment was sold at a profit of 6% and the rest at a loss of 3%. If however, there was an overall profit of Rs 540, the value of the consignement was ........................





Answer

Cost price of consignment = y

so, (2/3)y x 1.06 + (1/3)y x .97 = 540 + y

or, (2.12 + .97)y = 540 x 3 + 3y

or, 0.09y = 540 x 3 

or, y = 18000