1. The problem states that the weight $y$ of a goldfish is modeled by the linear equation $$y = 10x - 2000$$ where $x$ is the length in millimeters. 2. We are asked to find the weight when the length $x$ is 302 millimeters. 3. Substitute $x = 302$ into the equation: $$y = 10(302) - 2000$$ 4. Calculate the multiplication: $$y = 3020 - 2000$$ 5. Simplify the subtraction: $$y = 1020$$ 6. Therefore, the predicted weight of the goldfish with length 302 mm is 1020 grams.