Question

a vessel has 30 litres of a mixture of milk and water containing 80% milk. how many liters of water must be added to the vessel to reverse the ratio of milk and water?

Answer 1

In the initial mixture,
Amount of milk = 30 × 80/100 = 24
Amount of water = 30 - 24 = 6

Ratio of milk and water in the initial mixture is
80 : 20 = 4 : 1
Let amount of water to be added is x to make the ratio 1 : 4
Then, 24 : 6+x = 1 : 4
$\frac{24}{6 + x} = \frac{1}{4} \\ x = 96 - 6 = 90$

Answer 2

In the initial mixture,

Amount of milk = 30 × 80/100 = 24

Amount of water = 30 - 24 = 6

Ratio of milk and water in the initial mixture is

80 : 20 = 4 : 1

Let amount of water to be added is x to make the ratio 1 : 4

Then, 24 : 6+x = 1 : 4

24 / 6 + x = 1 / 4

x = 96 - 6 = 90

6+x / 24 = 4/1

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x=96−6=90

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