NAvinash wrote:

Bunuel, I tried to convert this into a equation : 20% [10 Lit] =

25% [ 10 +W] and it is giving incorrect answer. After looking at clarification I can understand the solution but appreciate if you can advise what is wrong in my equation.

Hello

NAvinashIMO, you are slightly incorrect there. See the highlighted portion in

RED. You correctly understood that you have to reduce the percentage of alcohol to 25% (or by 75%), but that reduction has to be in the given percentage of alcohol, that is,

25% of 20% of alcohol in the solution = 5% of alcohol in the solution. So, your equation will be;

20% [10 L] = 5% [10+W]Which will get you W = 30L.

I hope it helped.