Question

450 litres of a mixture of milk and water contain the milk and water in the ratio 9 : 1. How much water should be added to get a new mixture containing milk and water in the ratio 3 : 1?

Answer 1

Answer: 90 litres of water should be added to get a ratio of 3:1.

Step-by-step explanation:

The ratio of milk and water in the initial mixture: 9:1

The volume of the initial mixture: 450 litres

So, it can be written as:

10 units( obtained from the given ratio) is equal to 450 litres

Therefore, 9 units = (450/10 ) × 9 = 405 litres

So, the volume of milk in the initial mixture is 405 litres.

Also, 1 unit = 45 litres

So, the volume of water in the initial mixture= 45 litres.

In the second case:

New ratio( M:W) = 3:1

Let x be the amount of water added

Forming the new ratio( M:W) -

405 : 45+x = 3:1

So, 405/45+x = 3

or, 405 = 3(45+x)

or, 405 = 135 + 3x

or, 3x = 405-135 = 270

or, x = 90

Therefore, 90 litres if water is to be added to get the new ratio.