Final answer:
The length of hair measured at 5 inches is represented as 5.0 inches in decimal. Measurements like hair are often done in inches or micrometers, and proportions are used to compare different scales of lengths.
Step-by-step explanation:
The length of your hair is 5 inches, which is to be written as a decimal. In decimal form, 5 inches is simply written as 5.0 inches. This is because an inch is a standard unit of measurement and does not need to be converted or represented in another form when expressing in decimal. When we measure small things, like the width of a human hair or the length of a crayon, we often use inches as the unit. For example, the average diameter of a human hair is about 60 micrometers (µm), which is 6.0 × 10-5 meters expressed in scientific notation. When working with proportions and scale models, comparing scale lengths to actual lengths, we use ratios expressed in the same units, for instance, 0.5 inches to 20 miles can be compared to 8 inches to an unknown number of miles using a proportion.