Data Sufficiency (DS) | Re: A mixture consists of two spirits A and B; A evaporates at the rate of

Alternatively you can use the following method:
We can solve this problem by equating the amounts of either A or B before and after evaporation.
CiVi = CfVf

As per the question, 20ml of A and 30ml of B have evaporated.

Lets solve for A.

(1)
Ci=4/9
(4/9) * x = Cf * (x-20)
We need to find x (total volume after 10 mins)
Since we do not have the value of Cf we cannot solve for x.
Insufficient
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