Question

787.5
11. A 60 liter mixture of milk and water contains
20% water. How much water must be added to
make water 20% in the mixture?
192
200
190
210​

Answer 1

Mixture =60 L , 10% water in it

Water=(60×10)/100 =6 L

Milk 60–6=54 L

Let x L water to be mixed

Then milk=54 L, water (6+x) L ,

Total mixture =(60+x ) L , which contains 20% water.

So, (6+x)×100/(60+x) =20

Or, 600+100x=20(60+x)

Or, 600+100x=1200+20x

Or, (100–20)x=1200–600

Or, 80x=600

Or, x=600/80=7.5

So 7.5 L water to be mixed