Final answer:
The actual length of an item based on a scale model is determined by using the scale factor. For a model ship 15 inches long with a scale factor of 1 inch = 6 feet, the actual ship would be 90 feet long.
Step-by-step explanation:
To calculate the actual length of an item based on a model, you use the given scale factor. For instance, if the scale factor of a model ship is 1 inch = 6 feet, then a model that is 15 inches long represents an actual ship that is 15 times 6 feet long, which is 90 feet. Understanding this concept helps with various scaling problems, such as determining the length of a model based on the actual size or finding the actual size based on the model's dimensions.
Using a variety of examples helps to reinforce the concept of scale models. For example, if the scale model of a mountain is 2.75 feet tall and the scale is 1/4 inch = 50 feet, we can determine the actual mountain's height by setting up a proportion and cross-multiplying to find the answer. Converting between different units of measurement is also essential when working with scale models and their respective real-world objects.