Let the quantity of solution A and B mixed be ‘x’ and ‘y’ units respectively % of salt in solution A = 20% % of salt in solution B = 50% % of salt in final solution = 30% Hence, we can write, ⇒ 20x + 50y = 30(x + y) ⇒ 30x - 20x = 50y - 30y ⇒ 10x = 20y ⇒ x = 2y ⇒