5.3 Dot Plots

Lesson 5.3 Dot Plots

Algebra 2

Dot Plots

Dot plots are a convenient way to look at how data is distributed across its values. You can see which values show up most often and how spread out the data is.

Dot plots are best used with numerical data all rounded the same. Whole numbers are most convenient, but decimals can work, too.

Dot Plots

Each dot in a dot plot is a data point plotted along a horizontal axis. Duplicate values are stacked. In this plot, there are 50 data values represented. The value 6 is present 4 times in the set.

Please answer the next three questions

Thank you!

Multiple Choice

What is the highest score in the class?

• 88%

• 100%

• 13

• 98%

Multiple Choice

How many students spent 7 hours doing homework that week?

• 1

• 3

• 5

• 6

Multiple Choice

How many students read no books (zero) last summer?

• 6

• 1

• 4

• 3

Dot Plots

You can also count across multiple columns to answer questions about ranges of responses. For example:

How many times did an even number get picked? Count up the even columns.

 $3+7+6+4+2=22$ times

Please answer the next six questions

Thanks again!

Multiple Choice

How many people have 4 or more pets?

• 8

• 3

• 6

• 4

Multiple Choice

How many students scored 93% or less?

• 6

• 16

• 14

• 13

Multiple Choice

How many students scored between 95 and 100?

• 6

• 6

• 9

• 14

Multiple Choice

How many students received a score in the 80's?

• 2

• 10

• 14

• 27

Multiple Choice

What is the greatest amount of time a student spent doing his homework?

• 2 hours

• 1 hour

• 6 hours

• 10 hours

Multiple Choice

How many people have two or less books in their desk?

• 4

• 5

• 6

• 7

Building a Dot Plot

Building a dot plot is just a matter of plotting data points on a number line and stacking any duplicates. It's important that your number line be evenly spaced, so it's alright for there to be gaps.

Building a Dot Plot

The data set doesn't even have to be ordered. You just create a number line that will fit all the data and place a dot above the number for each value in the data set.

Last Question! Choose the dot plot that best matches the data.

Almost done!

Multiple Choice

Thank you for watching

You are now dot plot experts!