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A solution prepared by a chemist, in which the volume of water is 30% of the total volume. After pouring 5 liters of water in this solution, it was observed that the volume of water has increased to 40%. How many liters was the water in the initial solution?

A solution prepared by a chemist, in which the volume of water is 30% of the total volume. After pouring 5 liters of water in this solution, it was observed that the volume of water has increased to 40%. How many liters was the water in the initial solution? Correct Answer 9

Given:

Initially, the volume of water is 30% of the total volume.

After pouring 5 liters of water in this solution, the volume of water has increased to 40%.

Calculation:

Let the total mixture be 10x

The volume of water initially = 30/100 × 10x = 3x

After adding 5 litres of water,

⇒ (3x + 5)/7x = 40/60

⇒ (3x + 5)/7x = 2/3

⇒ 9x + 15 = 14x

⇒ x = 3

The volume of water initially = 3x = 3 × 3 = 9 litres

∴ 9 litres was the water in the initial solution.

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