Answer:the interquartile range (IQR) of the data set {1, 3, 4, 6, 6, 7, 9, 11, 12, 13} is 7.
Explanation:1. Arrange the data set: {1, 3, 4, 6, 6, 7, 9, 11, 12, 13}2. Find the median (Q2): The median is 6 (average of the two middle values).3. Find the lower quartile (Q1): Median of {1, 3, 4, 6, 6} is 4.4. Find the upper quartile (Q3): Median of {9, 11, 12, 13} is 11.5. Calculate the IQR: Q3 - Q1 = 11 - 4 = 7.
