Bunuel
A tank contains a mixture of 200 litres of wine and water. 20% of the mixture is water and the remaining is wine. How many litres of water should be added to the mixture to increase the percentage of water to 25% in the new mixture?
A 13 1/3
B 16 1/3
C 19 1/3
D 22 1/3
E 25 1/3
By adding water, we are keeping wine constant. Originally we had \(80\% * 200 = 160 L\) of wine, we want that to be 75% of the new mixture.
Thus \(\frac{160}{75\%} = 160*\frac{4}{3} = \frac{640}{3} = 200 + \frac{40}{3}\) is the new mixture's volume. Then we added \(\frac{40}{3}\) which is choice A.
Ans: A
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