Lesson 2: Pre-Visit Batting Average Ups and Downs

Objective: Students will be able to:

• Use multiple data sets to determine the overall success rate of a particular activity.
• Select and create appropriate graphs representing data sets.

Time Required:

1 class period

Advance Preparation:

o Set up 4 stations around the classroom as follows:
o Station 1: Quarters or other small change
o Station 2: A pair of dice
o Station 3: A deck of playing cards
o Station 4: Marbles of different colors in a opaque bag

Materials Needed:

- Copies of the "Batting Average Boost" worksheet (included) – 1 for each student
- Prepare packets of “Day 2 Station Worksheets” (included). Make enough packet copies for students to work in pairs or small groups.
- Completed packets of “Day 1 Station Worksheets” from Lesson 1.
- Scrap Paper
- Graph Paper
- Calculators
- Pencils

Vocabulary:

Batting Average – A measure of a batter’s performance, calculated as the number of hits divided by the number of times at bat
Statistics - A branch of mathematics dealing with the collection, analysis, interpretation, and presentation of numerical data

1. Review the formula for finding a batting average: Batting Average = Hits/At Bats.

2. Give students the following problem:
o In one game Josh Hamilton gets 2 hits in 5 at bats. At the end of the game, what would be his new batting average?

3. Go over the problem. 2 hits/5 at bats = .400. (Remind students that batting average is always expressed to the thousandths place. In this case, zeroes must be added.)

4. Explain that if the 1-day average is greater than someone's overall average, the overall average will increase. If the 1-day average is lower than the overall average, the overall average will decrease.

5. Ask students, "Let's say that Josh Hamilton had an overall average of .302 before this game. What happened to his overall average after the game?"
Since .400 > .302, his overall average will go up.

6. How much a player's batting average increases or decreases depends on the number of at bats the player already has. At the beginning of the season, a player's one-day average will have a greater effect on his overall average. At the end of the season, a one-day average will have a smaller effect.

7. You may choose to have students complete the "Batting Average Boost" worksheet before moving on to the activity, or you may assign it for homework.

8. Introduce the activity.

1. Have students get together in the same pairs or groups they worked with during the activity in Lesson 1.

2. Pass out each group’s completed “Day 1 Station Packet,” and provide each group with a “Day 2 Station Packet.”

3. Explain that students are to work through each station again, and perform each activity five more times, documenting results and determining today’s average rate of success for each station.

4. Groups should then determine if their 2nd day’s average would make their overall activity average go up or go down, and what the new overall activity average will become.
Provide students with the following example: Let’s say Jason and Max had a .500 (5/10) average on Station 1 from Day 1. On Day 2, their average is .400 (2/5). Their overall average will go down, and the new overall average will become .467 (7/15).

5. Remind students to round each average to the nearest thousandth.

6. Assist students with stations as necessary.

Conclusion:
To complete this lesson and check for understanding, come together as a class and have students compare their 2-day averages for each station. Then, total the aggregate data from each station. Discuss which type of graph would be the best fit for each station’s data set. Have students make the appropriate graphs for each station.

CCSS.Math.Content.6.RP.A.1 Understand the concept of a ratio and use ratio language to describe a ratio relationship between two quantities.

CCSS.Math.Content.6.RP.A.2 Understand the concept of a unit rate a/b associated with a ratio a:b with b ≠ 0, and use rate language in the context of a ratio relationship.

CCSS.Math.Content.6.RP.A.3 Use ratio and rate reasoning to solve real-world and mathematical problems, e.g., by reasoning about tables of equivalent ratios, tape diagrams, double number line diagrams, or equations.

CCSS.Math.Content.6.NS.B.2 Fluently divide multi-digit numbers using the standard algorithm.

CCSS.Math.Content.6.EE.A.2 Write, read, and evaluate expressions in which letters stand for numbers.
• CCSS.Math.Content.6.EE.A.2a Write expressions that record operations with numbers and with letters standing for numbers.

CCSS.Math.Content.6.EE.B.6 Use variables to represent numbers and write expressions when solving a real-world or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set.

CCSS.Math.Content.6.SP.A.1 Recognize a statistical question as one that anticipates variability in the data related to the question and accounts for it in the answers.

CCSS.Math.Content.6.SP.B.5 Summarize numerical data sets in relation to their context, such as by:
• CCSS.Math.Content.6.SP.B.5a Reporting the number of observations.
• CCSS.Math.Content.6.SP.B.5b Describing the nature of the attribute under investigation, including how it was measured and its units of measurement.

CCSS.Math.Content.7.RP.A.1 Compute unit rates associated with ratios of fractions, including ratios of lengths, areas and other quantities measured in like or different units.

CCSS.Math.Content.7.EE.B.3 Solve multi-step real-life and mathematical problems posed with positive and negative rational numbers in any form (whole numbers, fractions, and decimals), using tools strategically. Apply properties of operations to calculate with numbers in any form; convert between forms as appropriate; and assess the reasonableness of answers using mental computation and estimation strategies.

CCSS.Math.Content.7.EE.B.4 Use variables to represent quantities in a real-world or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities.

CCSS.Math.Content.8.EE.C.7 Solve linear equations in one variable.