Question

A mixture of go liter of milk and water
contains 15%is water. How much water should
be added so that the percentage of water become
20%​

Answer 1

40 liters of milk-water mixture contains 10% water. So it contains 90% milk.

So amount of milk in the mixture= 40 x0.9=36 liter.

Now on adding 'X' liters of water the % of water increases to 20% . Or the % of milk decreases to 80% .

So (40+X) x 0.8= 36.

So upon solving the equation 32+0.8X =36 (or)

0.8X=36–32=4.

So X= 4/0.8= 5

So on adding 5 liters of water to the above milk-water mixture the new milk-water mixture will contain 20% water. ==============================