Correct Answer - Option 3 :
\(2\frac{2}{9}\)
Calculation:
5% of 40 liters
⇒ 5/100 × 40
⇒ 2 liters
In total mixture,
Out of 40 liters, water is 2 liters.
⇒ Milk = 40 – 2 = 38 liters
Now when water is 10% then milk will be 90%
According to the question,
⇒ 90% = 38 liters
⇒ 10% = 38/9 liters
Increased quantity of water,
⇒ 38/9 – 2 = (38 – 18)/9
⇒ 20/9
⇒ \(2\frac{2}{9}\)
∴ The amount of water that needs to be added is \(2\frac{2}{9}\)liters.