Help solve using gregs mixture trick

How many ounces of water must be added to
a 30-ounce solution that is 40 percent
alcohol to dilute the solution to 25 percent
alcohol?

https://gmatclub.com/forum/how-many-ounces-of-water-must-be-added-to-a-30-ounce-solution-that-is-240749.html

Yes that’s the normal way of solving the problem, I was hoping to get a solution using greg’s mixture problem trick

Solution 1 - Mixed - Water
40% - 25% - 0%

\frac{water}{Solution} = \frac{distance (solution - mixed)}{distance (mixed - water)}
\frac{water}{30} = \frac{40 - 25}{25 - 0}
\frac{water}{30} = \frac{15}{25}
water = \frac{15 * 30}{25} = 3 * 6 = 18

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