Data Measures
Populations, Samples, and Inferences
Box Plots
Dot Plots
100

What is the median?

4

100

Marcy wants to know what type of book is most commonly checked out by visitors of the public library. She surveys people in the children's reading room between 1:00 and 2:00 on Saturday.

What is the population of her study?

Visitors of the public library.

100

What is the median commute time for this sample?

30 minutes

100

What is the mode number drawn in this sample?

4

200

What is the mode?

7

200

Marcy wants to know what type of book is most commonly checked out by visitors of the public library. She surveys people in the children's reading room between 1:00 and 2:00 on Saturday.

Is her sample representative of the population? Why or why not?

No (because not all of the visitors go to the children's reading room)

200

What is the range in weight for this sample of apples?

40 grams (115-75)

200

What is the median number of finger puppets made in this sample?

1 puppet

300

What is the range?

3.5

300

Michael surveyed a random sample of 60 students in his school about the number of sports they play and found that 15 play exactly one sport. How many of the 300 students in his school can he infer play exactly one sport?

75 students   (15/60=75/300)

300

What is the IQR for the box plot?

8 donuts (12-4)

300

To the nearest tenth, what is the mean number of photographs taken?

2.6 photographs (47/18)

400

What is the IQR?

3

400

In a representative sample of 150 spectators, 50 said they attended 5 or more games. How many of the 2,400 spectators in total can we assume attended 5 or more games?

800 spectators  (50/150 = 800/2400)

400

Use the measures of center (medians) to make a comparative inference about the aquarium events.

The median of the movie is 85 and the median of the live show is 80, so there are generally more visitors at the movie.

400

Use the means to make a comparative inference about numbers of siblings.

The mean of the teachers is 2.9 and the mean of the students is 3.35, so in general the students have more siblings than the teachers do.

500

To the nearest tenth, what is the MAD?

2.7

500

Pam surveyed 18 students at her school about their favorite classes. Of the students surveyed, 6 said their favorite class was English. How many of the next 12  students surveyed should she expect to pick English based on past data?

4 students   (6/18 = 4/12)

500

Use measures of variability (IQR and range) to make a comparative inference about the puppies.

The beagles have a range of 5 and an IQR of 3 and the collies have a range of 4 and an IQR of 2, so there is more variation among the weights of beagles and the weights of collies are more consistent.

500

Use range to make a comparative inference about the data.

The range of Set A is 4 and the range of Set B is 5, so Set A is more consistent and Set B has more variability.