In a 60-liter mixture of milk and water, the water content is 40%. How many litres of water should be added to increase the water content to 60%?

Correct option is B

Given:

The total mixture is 60 liters.

The water content is 40%, so the amount of water in the mixture is 40% of 60 liters, which is:

Water = $$0.40 \times 60$$​ = 24 liters

Solution:

Let n litre of water is added:

Water = 40%, then Milk = 60%

Milk = $$60\times \frac{60}{100}$$ = $$(60 + n) \times \frac{40}{100}$$​​

=> 36 = $$(60 + n) \times \frac{40}{100}$$

​​=> $$36 \times \frac{5}{2}$$ = (60 + n)

=> n = 90 - 60 = 30 litres

The amount of water that should be added is 30 liters.

Thus, the correct option is (b) 30 litres

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