# Box and Whisker Plots Unit 9 Lesson 7

• Slides: 19

Box and Whisker Plots Unit 9 Lesson 7

Order numbers 3, 5, 4, 2, 1, 6, 8, 11, 14, 13, 6, 9, 10, 7 l First, order your numbers from least to greatest: 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 13, 14

Median 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 13, 14 l Then find the median (from the ordered list): l Cross off one number from each side until you reach the middle number (or numbers). 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10 11, 11 13, 13 14

Median (continued): 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10 11, 11 13, 13 14 l If there are two numbers in the middle, Add those 2 middle numbers together: 6 + 7 = 13 l Then divide by 2: 13 ÷ 2 = 6. 5 l The median is 6. 5.

Quartiles (page 1) 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 13, 14 l Then split the numbers on left and right sides of the median: 1, 2, 3, 4, 5, 6, 6, │7, 8, 9, 10, 11, 13, 14

Quartiles (page 2) 1, 2, 3, 4, 5, 6, 6, │7, 8, 9, 10, 11, 13, 14 l Find the median for each half: 1, 2, 3, 4, 5, 6, 6 │ 7, 8, 9, 10, 11, 13, 14 1, 2, 3, 4, 5, 6, 6 │ 7, 8, 9, 10, 11 13, 13 14 Left Median = 4 Right Median = 10

Quartiles (page 3) 1, 2, 3, 4, 5, 6, 6 Left Median = 4 l The │ 7, 8, 9, 10, 11 13, 13 14 Right Median = 10 left median is called the LOWER QUARTILE. l The right median is called the UPPER QUARTILE.

Number line 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 13, 14 l Draw a number line from the smallest to the largest number without skipping any numbers. 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Quartiles on number line 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 13, 14 l Put circles at the LOWER and UPPER Quartiles. 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Box on Quartiles on number line 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 13, 14 l Draw a box connecting the circles at the LOWER and UPPER Quartiles. 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Median on number line 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 13, 14 l Put 1 a circle at the median (6. 5). 2 3 4 5 6 7 8 9 10 11 12 13 14

Median on number line 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 13, 14 l Draw a line connecting the median to the box. 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Low and high numbers 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 13, 14 l Put 1 circles at the high and low points. 2 3 4 5 6 7 8 9 10 11 12 13 14

Low and high numbers 1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 11, 13, 14 l Draw lines that connect the high and low points to the box. 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Box and Whisker Plot 3, 5, 4, 2, 1, 6, 8, 11, 14, 13, 6, 9, 10, 7 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Here is the completed Box and Whisker Plot!

Colby graphed some data as shown in this box-and-whisker plot. Which statement is true about Colby’s data? The range of the data is 25. B. One-half of the data is below 65. C. The median of the data is 60. D. Three-fourths of the data is below 90. A. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Which of the following is not true about the box-and-whisker plot shown below? The inter-quartile range is 8 B. The upper quartile is -2. C. The median of the data is 1. D. The lower extreme is -9. A. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Interpreting Box and Whisker Diagrams What can you say about the ages of the shoppers and what kind of shop they are? Dressnice has a much lower median age, so the shoppers are younger 75% of the Dressnice shoppers are younger than 75% of the Clotheswell shoppers Clotheswell has broader appeal because the IQR is bigger Dressnice is a shop for younger people, perhaps more fashionable

Practice l Page l #1 -20 326 -327