Soy Sauce Fraction Mixture Problem

In a cooking class, a teacher instructs students to use a special sauce that requires a mixture of various fractions of ingredients. The recipe calls for:

- $\f\frac{2}{3}$ cup of soy sauce

- $\f\frac{3}{4}$ cup of vinegar

- $\f\frac{1}{2}$ cup of sesame oil

During the class, one student mistakenly added an extra $\f\frac{1}{4}$ cup of vinegar into the mix. What fraction of the total mixture does the soy sauce represent after the error has been made?