Final answer:
Two rectangles with corresponding sides of 4 and 8 inches and 2 and 4 inches are in proportion, as their length and width ratios are both 1/2. Similarly, speeds of 55 and 110 miles per hour are in proportion. Unit scales are also examples of proportions, such as a 1/50 scale model which means that 1 inch on the model represents 50 inches in reality.
Step-by-step explanation:
A simple example of two things that are in the same proportion would be if you have two rectangles of varying sizes but maintaining the same shape. For instance, if the length of the first rectangle is 4 inches and the width is 2 inches, and the length of the second rectangle is 8 inches and the width is 4 inches, the two rectangles are in proportion since both length and width ratios are equal, i.e., length ratio (4/8) is the same as the width ratio (2/4), which simplifies to 1/2 in both cases. Another example could be the comparison of speed in miles per hour; if one car travels at 55 miles per hour and another at 110 miles per hour, their speeds are in proportion (55/110 simplifies to 1/2).
In the context of a unit scale, if the actual length of an object is 50 inches and a scale model is 1 inch, the proportion, or unit scale, is written as 1/50. A proportion is exhibited when two such ratios are equivalent, like 1/50 and 0.5/25 (which also simplifies to 1/50), indicating that the scale models are proportional to the actual object.