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Anna's class is having a holiday party, and she is in charge of bringing juice. She decides to bring powdered juice mix and add water to it at school. There is a proportional relationship between the volume of water Anna uses to make the juice (in liters), x, and the number of scoops of juice mix she uses, y.
To make the juice, Anna combines 4 liters of water and 12 scoops of juice mix. Write the equation for the relationship between x and y.
What is y = 3x