# ﻿Using Dot Plots to Answer Statistical Questions

Warmup

Activity #1

Exploring Dot Plots.

• Click in the boxes show mean, show meanshow mode(s) below. Note where each of them are located. ​
• Move the data sample button to the left. ​

Which of the central tendencies is affected the most?

Activity #2

Using Dot Plots to Answer Statistical Questions.

A keyboarding teacher wondered: “Do typing speeds of students improve after taking a keyboarding course?” The teacher recorded the number of words that her students could type per minute at the beginning of a course and again at the end. The two dot plots below show the two data sets.

(1.) Based on the dot plots, do you agree with each of the following statements about this group of students? (After selecting your answer click on the “Text” tool and then click in the box to type in your explanation.)

(2.) Explain why her question is a statistical question.

(3.) Overall, how fast would you say that the students typed after completing the course? What would you consider the center of the end-of-course data?

Activity #3

`Exercise Questions.`

Twenty-five sixth-grade students were asked to estimate how many hours a week they spend talking on the phone. This dot plot represents their reported number of hours of phone usage per week.

(1.) How many of the students reported not talking on the phone during the week? Explain how you know.

(2.) What percentage of the students reported not talking on the phone?

(3.) What is the largest number of hours a student spent talking on the phone per week?

(4.) What percentage of the group reported talking on the phone for this amount of time?

(5.) How many hours would you say that these students typically spend talking on the phone?

(6.) How many minutes per day would that be?

(7.) How would you describe the spread of the data? Would you consider these students’ amounts of time on the phone to be alike or different? Explain your reasoning.

Challenge #1

Use one of these suggestions (or make up your own). Research to create a dot plot with at least 10 values. Then, describe the center and spread of the distribution.

• Points scored by your favorite sports team in its last 10 games
• Length of your 10 favorite movies (in minutes)
• Ages of your favorite 10 celebrities.

Challenge #2

Twenty-five students were asked to rate—on a scale of 0 to 10—how important it is to reduce pollution. A rating of 0 means “not at all important” and a rating of 10 means “very important.” Here is a dot plot of their responses.

Explain why a rating of 6 is not a good description of the center of this data set.

Challenge #3

Three sets of data about ten sixth-grade students were used to make three dot plots. The person who made these dot plots forgot to label them.

Quiz Time