In this Grade 9 Saxon Algebra 1 lesson from Chapter 7, students learn how to organize and display numerical data using stem-and-leaf plots and histograms. The lesson covers constructing stem-and-leaf plots with stems, leaves, and keys, then using those plots to calculate statistical measures including median, mode, range, and relative frequency. Students also learn to build histograms that display data frequency across equal intervals, including using a graphing calculator for real-world data sets.
Section 1
📘 Displaying Data in Stem-and-Leaf Plots and Histograms
A stem-and-leaf plot is a data display that uses some digits as "stems" and others as "leaves."
Next, you’ll construct and interpret these plots to find key statistical measures and reveal the hidden story within a set of numbers.
Section 2
Stem-and-leaf plot
A data display that uses some digits as "stems" and others as "leaves." The "stems" have a greater place value than the "leaves."
Think of it as sorting data by its first digits (the stem) and listing the last digits (the leaves) next to it. This makes it super easy to see how your numbers are spread out, like finding clusters or gaps in test scores! It is a fantastic way to organize data while keeping all the original values visible.
2|3, 8, 3|5, 4|1, 1. Key: 2|3 = 23.7|8, 8|1, 5, 5, 9|2. Key: 8|1 = 81.5|3, 5, 6|4, 9. Key: 5|3 = 53 degrees.Section 3
Example Card: Making a Stem-and-Leaf Plot
Let's see how a stem-and-leaf plot can turn a messy list of numbers into a clear picture.
Example Problem
The list shows scores for a recent biology test. Create a stem-and-leaf plot of the data.
Section 4
Example Card: Analyzing a Stem-and-Leaf Plot
Now that our data is organized, let's find its key statistical measures.
Example Problem
Use the plot of ages at a family reunion to find the median, mode, range, and relative frequency of age 71.
Section 5
Histogram
A histogram is a bar graph that displays the frequency of data in equal intervals. Each bar must be the same width and should touch the bar(s) next to it.
Imagine sorting data into 'buckets' of the same size, like ages 10-19, 20-29, etc. A histogram uses touching bars to show how many data points fall into each bucket. The taller the bar, the more data is in that group! It provides a great visual summary of the data's distribution without showing every single value.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter
Expand to review the lesson summary and core properties.
Section 1
📘 Displaying Data in Stem-and-Leaf Plots and Histograms
A stem-and-leaf plot is a data display that uses some digits as "stems" and others as "leaves."
Next, you’ll construct and interpret these plots to find key statistical measures and reveal the hidden story within a set of numbers.
Section 2
Stem-and-leaf plot
A data display that uses some digits as "stems" and others as "leaves." The "stems" have a greater place value than the "leaves."
Think of it as sorting data by its first digits (the stem) and listing the last digits (the leaves) next to it. This makes it super easy to see how your numbers are spread out, like finding clusters or gaps in test scores! It is a fantastic way to organize data while keeping all the original values visible.
2|3, 8, 3|5, 4|1, 1. Key: 2|3 = 23.7|8, 8|1, 5, 5, 9|2. Key: 8|1 = 81.5|3, 5, 6|4, 9. Key: 5|3 = 53 degrees.Section 3
Example Card: Making a Stem-and-Leaf Plot
Let's see how a stem-and-leaf plot can turn a messy list of numbers into a clear picture.
Example Problem
The list shows scores for a recent biology test. Create a stem-and-leaf plot of the data.
Section 4
Example Card: Analyzing a Stem-and-Leaf Plot
Now that our data is organized, let's find its key statistical measures.
Example Problem
Use the plot of ages at a family reunion to find the median, mode, range, and relative frequency of age 71.
Section 5
Histogram
A histogram is a bar graph that displays the frequency of data in equal intervals. Each bar must be the same width and should touch the bar(s) next to it.
Imagine sorting data into 'buckets' of the same size, like ages 10-19, 20-29, etc. A histogram uses touching bars to show how many data points fall into each bucket. The taller the bar, the more data is in that group! It provides a great visual summary of the data's distribution without showing every single value.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter