Final answer:
Rachel used a scale of 1:5 for the scale drawing of the school library, as determined by comparing the scale drawing length (16 inches) to the actual library's length (80 feet), which is equivalent to 960 inches.
Step-by-step explanation:
To determine which scale Rachel used to create the scale drawing of the school library, we need to set up a ratio that compares the scale drawing's length to the actual library's length. We have the scale drawing length as 16 inches, and the actual library's length as 80 feet.
First, we need to convert the actual library length from feet to inches, since the scale drawing is measured in inches. There are 12 inches in a foot, so the actual library length in inches is 80 feet times 12 inches per foot, which equals 960 inches.
Now, we can write the ratio of the scale length to the actual length in inches: 16 inches (scale) / 960 inches (actual). Simplifying this ratio by dividing both the numerator and the denominator by 16 gives us 1 inch (scale) / 60 inches (actual), which when further simplified by dividing both by 12 is 1 inch (scale) / 5 feet (actual).
So, the scale that Rachel used to create the scale drawing of the school library is 1:5, which matches option A.