8.2 Visualizing Data

Recall the example, in which a teacher recorded the responses on the first question of a multiple choice quiz, with five possible responses (A, B, C, D, and E). The raw data was as follows:

We computed a frequency distribution that looked like this:

$Proportion of a category = Category frequency / Total number of data units$

Now, let's compute the proportions for each category.

A collector of trading cards records the sale prices (in dollars) of a particular card on an online auction site, and puts the results in a stem-and-leaf plot:

Answer the following questions about the data:

1. How many prices are represented?
2. What prices represent the five most expensive cards? The five least expensive?
3. What is the full set of data?

An entomologist studying crickets recorded the number of times different crickets (of differing species, genders, etc.) chirped in a one-minute span. The raw data are as follows:

Construct a stem-and-leaf plot to visualize these results.