Final answer:
To shade 25%, you shade a quarter of the total, whether that is squares on a grid, portions of a given distribution, or segments of a sample. The context determines how to visually represent this percentage.
Step-by-step explanation:
The question you've asked appears to involve percentages and how they relate to shading parts of a diagram or a set of objects. When you have 25%, it means that you shade or represent a quarter of the total number of items or area. For example, if you have a grid of 100 squares and you need to shade 25%, you would shade 25 squares because 25 is 25% of 100. Similarly, if you are looking at percentages in other contexts such as flower colors or strata in samples, it means you take 25 parts out of every 100 parts to represent that portion. In the given example of a uniform distribution between 1.5 and 4, the area of 0.25 shaded represents the longest 25% of repair times, meaning the rightmost quarter of the graph is shaded.