Let x be the jug, [tex]\frac{1}{2}[/tex] for half-filled, y for the weight of the jug when empty.
∵ [tex]\frac{1}{2}[/tex]x + y = 2.6 kg
∵ x = 4 kg
∴ [tex]\frac{1}{2}[/tex] ⋅ 4 + y = 2.6 kg
∴ 2 + y =2.6 kg
∵ y = 2.6 - 2 = 0.6 kg
∴ The weight of the empty jug = 0.6 kg
