Learning Target:

I can develop an understanding of summarizing data by displaying data on a dot plot and histogram.

Success Criteria:In order to be successful I will…1) Plot data on a dot plot2) Plot data on a histogram3) Analyze dot plots and histograms

Dot Plots• A Dot Plot is a graphical display of data

using dots.

Dot Plot Example:Suppose 30 students are asked to pick their favorite color. Their responses are recorded in the dotplot below. Next we can analyze the dot plot.

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

* *

*

*

*

Red Orange Yellow Green Blue Indigo Violet

“How many students do you think liked yellow?”“How many students do you think liked indigo?”“What color was the most popular?”

Raven ran a 50 meter sprint in track 10 times and got the

following times in seconds.

27, 27, 28, 28, 25, 26, 27, 26, 26, 27

Using this data, create a dot plot where each dot

represents a different time that she ran.

25 26 27 28

Histogram: a graphical display of data using bars of different heights. (add to your notes)

• It is similar to a Bar Chart, but a histogram

groups numbers into ranges

In bar graphs are usually used to display categorical data.

Example Question:“What type of doughnuts do my friends prefer?”

Histograms on the other hand are usually used to present numerical data.

Example Question:“How much do adults weigh?”

654321

90 120 150 180 210

Example: Height of Orange TreesYou measure the height of every tree in the orchard in centimeters (cm)

The heights vary from 100 cm to 340 cm

You decide to put the results into groups of 50 cm:

● The 100 to just below 150 cm range,● The 150 to just below 200 cm range,● etc...

So a tree that is 260 cm tall is added to the "250-300" range.

And here is the result:

You can see (for example) that there are 30 trees

from 150 cm to just below 200 cm tall

Frequency

1.)

2.)

3.)

The histogram shows the heights of 21 students in a class, grouped into 5-inch groups.

How many students were greater than or equal to 60 inches tall?

Exit Ticket (3min)