1. Speeds of Animals The table lists the maximum running speeds of various animals. How can the data be displayed to show the distribution of the speeds? Animal Speed (miles per hour) Elk 45 Cheetah 70 Greyhound 39 Wildebeest 50 Quarter horse 47 Zebra 40 Giraffe 32 Coyote 43 In the Real World Stem-and-Leaf Plots 3.

2. Speeds of Animals The table lists the maximum running speeds of various animals. How can the data be displayed to show the distribution of the speeds? Animal Speed (miles per hour) Elk 45 Cheetah 70 Greyhound 39 Wildebeest 50 Quarter horse 47 Zebra 40 Giraffe 32 Coyote 43 A stem-and-leaf plot is a data display that helps you see the way data are distributed. You can use a stem-and- leaf plot to place data in increasing order. In the Real World Stem-and-Leaf Plots 3.

3. Display the speeds of the animals given in a stem-and-leaf plot. 1 The numbers vary from 32 to 70, so let the stems be the tens’ digits from 3 to 7. Let the leaves be the ones’ digits. 2 Write the stems first. Draw a vertical line segment next to the stems. Then record each speed by writing its ones’ digit on the same line as its corresponding tens’ digit. Animal Speed (miles per hour) Elk 45 Cheetah 70 Greyhound 39 Wildebeest 50 Quarter Horse 47 Zebra 40 Giraffe 32 Coyote 43 Making a Stem-and-Leaf Plot EXAMPLE 1 Stem-and-Leaf Plots 3. 3456734567 Key: 4 7 = 47 Unordered Plot Include a key to show what the stems and leaves represent. Ordered Plot 92 570 0 0 3 Make and ordered stem-and-leaf plot. 3 2 9 0 3 5 7 0 In the ordered plot, the leaves for each stem are listed in order from least to greatest.

4. Bicycle Stunt Competition The point totals (rounded to the nearest tenth) for the 20 participants in a bicycle stunt competition are listed below. The rider with the highest point total out of 100 points wins. 89.4 90 87.5 84.3 89.7 90.3 91.4 91 86.7 84.1 89.2 86 89.1 88.2 89.5 85.6 90.5 90.2 91.1 88.9 Use a stem-and-leaf plot to order the data. Then make a conclusion about the data. Begin by making an unordered stem-and-leaf plot. Because the point totals range from 84.1 to 91.4, the stems are the digits in the tens’ and ones’ places. The leaves are the digits in the tenths’ place. 84 85 85 87 88 89 90 91 Key: 87 | 5 = 87.5 Unordered Plot Ordered Plot More than half of the participants finished near the top, with 12 participants having point totals greater than 89. ANSWER SOLUTION Stem-and-Leaf Plots 3. Then make an ordered stem-and-leaf plot. 3 1 6 7 0 5 2 9 4 7 2 1 5 0 3 5 2 4 0 1 1 3 6 0 7 5 2 9 1 2 4 5 7 0 2 3 5 0 1 4 Interpreting a Stem-and-Leaf Plot EXAMPLE 2