Bar Graphs vs. Histograms Day 4 Unit 8 Bar Graphs vs. Histograms PRINCESS C. BARCEGA APG SCHOOL, MANAMA, BAHRAIN

What do you know about bar graph? double bar graph? Histogram?

Bar Graph A bar graph can be used to display and compare data The scale should include all the data values and be easily divided into equal intervals. Have you had a lot of experience with a bar graph?

How to interpret a Bar Graph? The bar graph shows Mr. Snowden’s students by gender and band membership. How many of Mr. Snowden’s students are band members? How many of Mr. Snowden’s students are not band members?

Double Bar Graph Can be used to compare two related sets of data Have you seen this type of graph before?

Double Bar Graph You will see double bar graphs a lot in reporting the weather on the news like the one to the left.

Histogram Histogram is a bar graph that shows the frequency of data within equal intervals. Frequency means how many or how much. There is no space in between the bars.

NO GAPS between Bars Continuous data

Bars are different in width Determined by Grouped Frequency Distribution

Since you have made bar graphs so much in lower math classes and you can probably infer how to make a double bar graph from the one I showed you… Let’s look at how to construct a histogram.

Creating Histograms Middle School Math Aligned to Common Core State Standards

Histograms Histograms are used to organize and interpret data. Histograms are often used with frequency tables to give a more visual view of the data. Each bar represents an interval that contains data. The height of the bar indicates the frequency of the data. Interval Tally Frequency 0-1 2-3 4-5 6-7 6-7

Create a frequency table. A professional football team scored the following number of points in games last season. Create a frequency table that reflects this information. 17, 24, 13, 16, 34, 38, 27, 13, 24, 13, 7, 0, 13, 10, 14, 0, 26, 23, 31, 7 First decide what intervals to use in your frequency table. Finding the minimum and the maximum really help to decide intervals. Intervals must be the same width! Intervals Tally Marks Frequency

Create a frequency table. A professional football team scored the following number of points in games last season. Create a frequency table that reflects this information. 17, 24, 13, 16, 34, 38, 27, 13, 24, 13, 7, 0, 13, 10, 14, 0, 26, 23, 31, 7 First decide what intervals to use in your frequency table. Scores Tally Marks Frequency 0 – 9  4 10 – 19   8 20 – 29 5 30 – 39  3

Build the histogram. Use the frequency table to help build the histogram. 17, 24, 13, 16, 34, 38, 27, 13, 24, 13, 7, 0, 13, 10, 14, 0, 26, 23, 31, 7 Scores Tally Marks Frequency 0 9  4 10 19   8 20  29 5 30  39  3

Build the histogram. Use the frequency table to help build the histogram. 17, 24, 13, 16, 34, 38, 27, 13, 24, 13, 7, 0, 13, 10, 14, 0, 26, 23, 31, 7 Scores Tally Marks Frequency 0 9  4 10 19   8 20  29 5 30  39  3