Question 1159883
Percents 7, 8, 12;
8 is smaller distance from 7 than from 12;
Most of the "mixture" will use the 7% vinegar.


Important Fraction,  {{{(12-8)/(12-7)=4/5}}}


Amount of the 7% vinegar,  {{{390(4/5)=312}}}{{{milliliters}}}

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