## Stats: Data and Models (3rd Edition)

The median is the average of middle two values of ordered list. Hence: Median = (66 + 66)/2 = 66 First quartile lies at 25% of data, so $Q_{1} = 65$ Third quartile lies at 75% of data, so $Q_{3} = 70$ The IQR is the difference between $Q_{3}$ and $Q_{1}$, so: $IQR = Q_{3} - Q_{1} = 70 – 65 = 5$ b. The mean is the sum of all values divided by number of values,so: $Mean = 8725/130 = 67$
The median is the average of middle two values of ordered list. Hence: Median = (66 + 66)/2 = 66 First quartile lies at 25% of data, so $Q_{1} = 65$ Third quartile lies at 75% of data, so $Q_{3} = 70$ The IQR is the difference between $Q_{3}$ and $Q_{1}$, so: $IQR = Q_{3} - Q_{1} = 70 – 65 = 5$ b. The mean is the sum of all values divided by number of values,so: $Mean = 8725/130 = 67$