In a barrel of 56 litres, the volume of milk is 62.5%. If the mixture requires to make 85.71% of milk, how much more amount of pure milk is needed to be added?
1). 91 litres
2). 88 litres
3). 90 litres
4). 85 litres
Total volume of mixture = 56 litres
Amount of milk in mixture = 62.5% of total volume = (5/8) × 56 = 35 litres
Let x litres of pure milk is added in the mixture.
To change the proportion of mixture,
Required amount of milk = 85.71% of total volume = (6/7) × (56 + x)
⇒ 35 + x = (6/7) × (56 + x)
⇒ 35 + x = 48 + 6x/7
⇒ x/7 = 13
⇒ x = 91 litres
∴ Amount of milk required = 91 litres