Correct Answer - Option 3 : 4.8%

**Given:**

Total amount of solution = 10 litres

Concentration of salt = 6%

Amount of water evaporated = 2 litres

**Formula used:**

Solution = solute + solvent

% of solute = (solute/solution) × 100

**Calculation:**

Remaining amount of solution = (10 – 2) litres

⇒ 8 litres

Amount of salt = (6/100) × 8

⇒ 48/100

⇒ 0.48 litres

Required percentage =Amount of salt/Total amount of solution × 100

⇒ 0.48/10 × 100

⇒ 4.8%

**∴ The required percentage is 4.8%**