Lesson - Dot plots

Learning Intention: create and interpret from a dot plot

Diagnostic:

Explanation:

Dot Plots

Scatter graphs are used for sets of data with two variables (e.g. Height and Weight)

Dot plots are useful for sets of data with one variable (e.g. Height). 

How to create a dot plot

1) Find your smallest and largest data point.

2) Make a horizontal axis that starts at one less than your smallest data point and ends at one more than your largest data point and has equally spaced steps in between.

3) Place one dot for each data point

Example:

Using the following data set: 12, 15, 16, 16, 14, 12, 14, 18, 19, 14, 15, 18, 16, 13, 15, 16, 13

The smallest data point is 12 and the largest is 19.

1) Draw the scale from 9 through 20

2) Plot the data points:

Tasks:

Complete Dot plots for the following sets of data: 

A) Handspan  measurements (cm)

22, 20, 23, 22, 19, 19, 20, 18, 21, 20, 20, 20, 18, 20, 20, 19, 16, 21, 21, 20, 22

B) Height (cm)

175, 171, 159, 173, 174, 178, 161, 168, 173, 166, 174, 171, 155, 176, 169, 154, 175, 181, 182, 160, 172

Diagnostic answers: