Answer:
17.5 kg of water.
Step-by-step explanation:
The amount of alcohol in the 15% solution = 20*0.15 = 3kg.
If 3 kg is equivalent to 8% solution
then 100% is 3*100 / 8 = 37.5 kg.
So the amount of water to be added to make 8% solution = 37.5 - 20
= 17.5 kg.
