Answer:
42 teaspoons of vinegar should be used
Explanation:
This question is solved by proportions, using a rule of three.
4 teaspoons of vegetable oil and 12 teaspoons of vinegar. 14 teaspoons of vegetable oil were used
So
4 teaspoons of vegetable oil - 12 teaspoons of vinegar
14 teaspoons of vegetable oil - x teaspoons of vinegar
So
![4x = 12*14](https://img.qammunity.org/2022/formulas/mathematics/college/x8jzdrsuh91mfj2rhgdb1lmm9yw3czixer.png)
Dividing both sides by 4:
![x = 3*14 = 42](https://img.qammunity.org/2022/formulas/mathematics/college/t61dl965ew6vm8yozvea7gbsoitz0p617l.png)
42 teaspoons of vinegar should be used