# Lesson 20

Memory Test

### Lesson Narrative

This lesson is optional. It gives students a chance to use the material they have learned in the unit with the final goal of comparing two populations, but may be shortened or skipped due to time constraints.

In this lesson, students apply what they have learned about probability, sampling, and comparing populations to analyze two data sets. Half of the class works with one data set while the other half of the class works with another. Students choose their own tools for selecting a sample at random (MP5) and calculate the mean, MAD, and a proportion to summarize their sample (MP2). Then students compare their results with a partner that had the other data set to construct an argument for whether there is a meaningful difference between the sets (MP3).

### Learning Goals

Teacher Facing

• Describe (orally) connections between sampling and probability.
• Generate a random sample, and use it to make inferences (in writing) about the population.
• Justify (orally and in writing) whether a given method produces a random sample.

### Student Facing

Let’s put it all together.

### Required Preparation

Print the Collecting a Sample blackline master. Provide one data set and one spinner for each student. If the spinners are used to select a random sample during the Sample Probabilities activity, provide a paper clip and sharpened pencil to use with the spinners. If possible, provide access to other tools for selecting a random sample from a 10-by-10 grid such as a 10-sided polyhedra or colored cubes and paper bags.

### Student Facing

• I can compare two groups by taking a random sample, calculating important measures, and determining whether the populations are meaningfully different.

Building On