WBJEE 2017 Chemistry Solved Paper

∵ We have to prepare maximum volume solution of 3N. (3N is same as 3M for HCl) Hence we will take all 500 ml of 2N solution and x ml of 5N solution.
∴ 500 × 2 + x × 5 = 3 (x + 500)
1000 + 5x = 3x + 1500
2x = 500
x = 250 ml
∴ Final volume = 500 + x = 500 + 250 = 750 ml