Final answer:
The interquartile range (IQR) of the highest daily temperatures for the past 15 years is calculated as 2 degrees Fahrenheit by subtracting the first quartile (97°F) from the third quartile (99°F). The provided answer options do not match the calculated IQR.
Step-by-step explanation:
The student asked for the interquartile range (IQR) of the data based on a dot plot showing the highest daily temperatures recorded for each of the past 15 years. To calculate the IQR, we'll need to find the first quartile (Q1) and the third quartile (Q3), and then subtract Q1 from Q3.
First, we organize the temperatures with the corresponding frequencies: 94°F (3), 95°F (2), 97°F (2), 98°F (4), 99°F (3), 100°F (1). We have 15 data points, so to find the Q1 position: (15+1)/4 equals to the 4th data point, which is 97°F, and for Q3: 3*(15+1)/4 equals to the 12th data point, which is 99°F.
Now we subtract Q1 from Q3 to find the IQR, which is 99°F - 97°F = 2°F. Therefore, the correct answer is 2 degrees Fahrenheit, which is not one of the options listed. It seems there is a mistake in the provided options, as none of them match the calculated IQR.