## Chapter 10

### Part 1: For the problem in the Teacher's Edition, page 250

Provide students with the Problem Worksheet (PDF file)

Ask the students to talk about how they figured out which day had the most children using slides. Here are some strategies they might suggest:

- Estimation for Friday: 200 + 300 + 300 + 300 = 1100

Estimation for Saturday: 400 + 600 + 400 + 300 = 1700

Estimation for Sunday: 200 + 200 + 200 + 400 = 1000

Saturday is the day that most children are using the slides. - The red, blue, and green slides are used way more on Saturday than the other two days. The green slide is used only about 10 times less on Saturday than Sunday. So Saturday is the day that the most children are using the slides.

Answer:

Saturday

### Part 2: Be an Investigator

A good time to do this investigation is after Lesson 5 on finding averages.

### Materials

- clock with second hand

#### Introducing the Investigation

Introduce the investigation by reading aloud the assignment at the top of the first page of the Description of Investigation and Student Report (PDF file), by having one of your students read aloud the assignment, or by having the students read the assignment individually.

Put students in groups of nine to work on the investigation.

#### Doing the Investigation

Have the groups collect data by having everyone jump for 10 seconds and counting the number of jumps they made.

Then have students work on their own to find the average. Have them give the average to the nearest whole number.

If you do not want to collect the data, use the following data from another group of students and have students find the average:

22

22

23

24

24

24

25

26

26

average: 24 (216 ÷ 9)

#### Student Report

The student report gives students an opportunity to show what they have done.

#### Extending the Investigation

- Have the students do the jumping contest with the whole class. Use calculators to compute the average.
- Have the students hold a jumping contest for children in one of the primary grades. Have them see if there is a difference in the average number of jumps in 10 seconds.