Final answer:
A scale ratio representing the error in measurement can be found by comparing the scale length to the actual size in consistent units. For a scale length of 0.5 inches representing 5 actual feet, the ratio is 0.5 inches to 60 inches (5 feet converted to inches). We then set this ratio equal to the intended scale, solving for the correct measurement or identifying any measurement error.
Step-by-step explanation:
When measuring an object with a scale model or drawing, we use a ratio or a fraction to represent the relationship between the scale measurement and the actual size.
In the context of this question, we are trying to find the error in measuring a certain length. If the scale length is 0.5 inches on the drawing, and it represents 5 feet in reality, then the scale ratio becomes 0.5 inches to 5 feet. Converting feet to inches to have consistent units (since there are 12 inches in a foot), we have the ratio as 0.5 inches to 60 inches.
This gives us the scale ratio as 0.5/60. To find the error as a fraction, we set this ratio equal to the length scale-to-actual proportion.
For instance, if the scale is supposed to be 1/20, the proportion should be 1/20 = 0.5/60. By cross-multiplying to solve for the actual figure or to identify a discrepancy, we can find the error in the measurement.