Final Answer:
The direct variation equation relating x miles and y kilometers is

Step-by-step explanation:
In this context, the relationship between miles and kilometers is established by the conversion factor 1 mile = 1.61 kilometers. To express this relationship as a direct variation equation, we set up the formula
where
represents the dependent variable (kilometers),
is the independent variable (miles), and
is the constant of variation. Since 1 mile is equivalent to 1.61 kilometers, the constant of variation
s 1.61. Therefore, the direct variation equation is
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This equation is based on the principle that as the number of miles (\( x \)) increases or decreases, the corresponding number of kilometers (\( y \)) will vary proportionally with a constant rate of 1.61. This mathematical representation allows for a straightforward conversion between miles and kilometers. For example, if
les, then
The equation provides a simple and effective way to convert distances between the two units.
Understanding and utilizing direct variation equations are essential in various scientific and engineering applications where conversions between different units are frequent. In this case, the direct variation equation
serves as a reliable tool for converting distances from miles to kilometers and vice versa, streamlining calculations and ensuring accuracy in unit conversions.