MATH SELF TUTOR SKILL: GRAPHS

Pennsylvania State Standard: Data and Probability M7.E.1 Formulate or answer questions that can be addressed with data and/or organize, display, interpret or analyze data.

Objectives Student will be able to create an accurate graph (bar, multiple – bar, line, multiple – line, histogram, stem-and-leaf plot) Students will be able to interpret data in order to answer questions.

NOPE! THERE ARE MORE! WOOHOO! Is that the only type of graph? Types of Graphs Bar Graph: a graph that uses horizontal or vertical bars to display countable data (set of information) NOPE! THERE ARE MORE! WOOHOO! Is that the only type of graph?

ANOTHER TYPE OF GRAPH! Multiple - Bar Graph: a bar graph that represents two or more sets of data.

Types of Graphs Line Graph: a graph that uses lines to show how data has changed over a period of time.

Even More Graphs! Multiple – Line Graph: a line graph that represents two or more sets of data and how they have changed over a period of time.

More and More Graphs! Histogram – a bar graph that shows the number of times data occur within certain ranges or intervals ONLY 1 MORE! SWEET!

Now lets learn how to make these graphs THE LAST GRAPH! Stem – and – Leaf Plot: a data display that shows groups of data arranged by place value. Now lets learn how to make these graphs

WHAT DO I HAVE TO DO TO MAKE A BAR GRAPH? Label your x and y axis Y axis is the vertical axis (up and down) X axis the horizontal axis (side to side) Number of Students (y axis) School Subject ( x axis)

WHAT DO I HAVE TO DO TO MAKE A BAR GRAPH? Give your graph a title! It should appear above your graph! Favorite School Subject

WHAT DO I HAVE TO DO TO MAKE A BAR GRAPH? Make sure your intervals are spaced evenly and follow a pattern! 14 12 10 8 6 4 2 Pattern: Every line you count by 2 (you can choose whatever pattern you want as long as it fits your data) Spacing: Y axis is every line ( you can choose to space your intervals however you want)

WHAT DO I HAVE TO DO TO MAKE A BAR GRAPH? Make sure your intervals are spaced evenly and follow a pattern! 14 12 10 8 6 4 2 Spacing: X axis is every other line Math Science History Reading

WHAT DO I HAVE TO DO TO MAKE A BAR GRAPH? Make sure your intervals are spaced evenly and follow a pattern! 14 12 10 8 6 4 2 Math Science History Reading Bars should be the same width and the same color!

WHAT DO I HAVE TO DO I INTERPRET A BAR GRAPH? 8b’s FAVORITE SCHOOL SUBJECT The TITLE will tell you what the graph represents. This graph is representing 8b’s favorite subject. 14 12 10 Number of Students (y axis) 8 6 4 2 Math Science History Reading School Subject

WHAT DO I HAVE TO DO I INTERPRET A BAR GRAPH? WHAT IS THE X AXIS TELLING US? 8b’s FAVORITE SCHOOL SUBJECT Number of Students The x axis is telling us the subjects that the students voted for. You can tell by the way the axis is labeled 14 12 10 8 6 4 2 Math Reading Science History School Subject

SAMPLE QUESTION! How many students choose Reading as their favorite subject ? 8b’s FAVORITE SCHOOL SUBJECT Number of Students 14 12 10 1.Find Reading on the x axis. 8 2.Follow the bar up until it stops. 6 3.Find the number on the y-axis that corresponds to where the bar ends. 4 2 8 students said that Reading is their favorite subject! Math Science History Reading School Subject

HOW DO I MAKE A MULTIPLE BAR GRAPH? You follow the same steps for making a bar graph Make sure you have two or more bars and key to show what each bar represents.

HOW DO I MAKE A MULTIPLE BAR GRAPH? Key = girls = boys 8th Grade’s Favorite Subject 12 Number of Students 9 6 Title 3 X and Y axis labeled Intervals evenly spaced Math Reading Science History Included Key School Subjects

Line Graph? How do you make one of those? It is simple. Remember a bar graph? You follow some of the same steps to get started. EASY! Title Label x and y axis Space intervals evenly

MAKING A LINE GRAPH Title Label axes Space intervals evenly Number of books I read each month! Title Label axes 7 6 5 Space intervals evenly 4 # of books 3 2 1 June July August September NOW FOR THE NEW ITEMS! Months

. . . . MAKING A LINE GRAPH Number of books I read each month! To graph your data, point a point on in the correct spot. MAKE SURE THAT IT IS IN THE CORRECT ROW AND COLUMN. . 7 . 6 . # of books 5 Sample Information: 4 . 3 I read 3 books in June. 2 I read 6 books in July. 1 I read 4 books in August. June I read 1 book in September. July August September Months

. . . . Then, using straight lines, connect your dots! MAKING A LINE GRAPH Then, using straight lines, connect your dots! Number of books I read each month! . 7 . 6 . # of books 5 4 . 3 2 1 June July August September Months

MAKING A MULTIPLE - LINE GRAPH Number of books people have read each month! Follow the same steps for making a line graph. MAKE SURE YOU INCLUDE A KEY TO IDENTITY WHAT EACH LINE REPRESENTS! . . . 7 . . 6 . . # of books 5 4 . 3 2 1 June July August September Months

MAKING A MULTIPLE - LINE GRAPH Number of books people have read each month! KEY = Susan = Cliff . . . 7 . . 6 . . 5 # of books 4 . 3 2 The purple line shows you how many books Susan read each month, while the red line shows how many Cliff read each month 1 June July August September Months

MAKING HISTOGRAMS! Making a histogram is very similar to making a bar graph So what is different? Lets check it out! Title on the top of the graph Label x and y axis Equal intervals.

MAKING HISTOGRAMS A histogram includes ranges. Salaries at A.B.C Toy Store A histogram includes ranges. 20 – 30 31 – 40 41 – 50 51 – 60 61 - 70 Salary for the year (in thousands)

MAKING HISTOGRAMS When drawing the bars in the histogram, there should be no spaces! Salaries at A.B.C Toy Store 20 15 Number of Employees 10 5 0 – 20 21 – 40 41 – 60 61 – 80 81 - 100 Salary for the year (in thousands)

Stem and Leaf Plots A stem and leaf plot is different than the other graphs. It does not include bars, lines, or intervals. A stem-and-leaf plot can help you compare data.

How do I Make a Stem and Leaf Plot? First, arrange your data from the minimum (least) to the maximum (greatest). Math test scores: 59, 70, 82, 84, 92, 96, 90, 100, 79, 73, 87 Math test scores arranged from minimum to maximum 59, 70, 73, 79, 82, 84, 87, 90, 92, 96, 100

How do I Make a Stem and Leaf Plot? The stem stands for the digit in the 10s place value. Math test scores arranged from minimum to maximum 59, 70, 73, 79, 82, 84, 87, 90, 92, 96, 100 Stem 5 7 8 9 10 If you have a number in which there is a place value greater than the 10s, include those in the stem.

How do I Make a Stem and Leaf Plot? Each Leaf stands for the digit in the ones place value. MAKE SURE YOU ARE PUTTING THEM IN ORDER FROM MINIMUM TO MAXIMUM Math test scores arranged from minimum to maximum 59, 70, 73, 79, 82, 84, 87, 90, 92, 96, 100 Leaf Stem 5 7 8 9 10 0, 3, 2, 4, 6