Section 6.7 Box-and-Whisker Plots Objective: Students will be able to draw, read, and interpret a box-and- whisker plot.
Five Number Summary 1. Minimum value 2. First Quartile (Q1) 3. Median (Q2) 4. Third Quartile (Q3) 5. Maximum Value
Five Number Summary (ctd.) 1. Minimum Value – Lowest value of data set 2. Q1 – Median of lower half of numbers 3. Q2 – Median of entire data set 4. Q3 – Median of upper half of numbers 5. Maximum Value – Highest value of data set
Finding the five number summary For the following problems, find the five number summary and then draw the box-and- whisker plot that represents the data.
5 Number Summary and Box- and-Whisker Plot (Ctd.) 1. 29, 36, 27, 34, 32, 29, 37, 26, 29, 29, 30, 35, 33, 26, 27
5 Number Summary and Box- and-Whisker Plot (Ctd.) 2. 2, 22, 19, 32, 17, 30, 18, 15, 27, 36, 18, 14, 23, 18, 24, 82
Interquartile Range (IQR) The interquartile range (IQR) is the range of the middle half of a set of data. To find the interquartile range, subtract the first quartile from the third quartile. IQR=Q3-Q1
Finding the IQR Using the data from the previous two examples, find the IQR of each set of data.
Outliers Outliers are extreme values in a value set. To find outliers, use the following formulas: Q1-(1.5xIQR) Q3+(1.5xIQR)
Finding outliers Using the data from the previous two examples, find the outliers of each set of data.
Assignment Box-and-Whisker Plots Five-Number Summary WS Page 378(11-22)