Help with Opening PDF Files

## Chapter 5

### Part 1: For the problem in the Teacher's Edition, page 108

Provide students with the Problem Worksheet (PDF file).

To find the average speed of the Concorde students need to divide 17,400 miles by 12. To find how many miles Amelia Earhart could have traveled in 12 hours, students need to find her average speed per hour by dividing 2,205 by 15. Then take the answer, 147, and multiply it by 12 to find how many miles Amelia Earhart could have traveled in 12 hours.

The average speed of the Concorde was about 1,450 miles per hour (mi/h).
Amelia Earhart could have traveled about 1,764 miles in 12 hours.

### Part 2: Be an Investigator

A good time to do this investigation is after Lesson 5 on division with greater numbers.

#### 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.

Ask, How would you find the average speed in miles per hour (mi/h) of one of these flights? (divide the distance by the amount of time)

Ask, Which average speed is not in terms of mi/h?(the Wright Brothers' average speed)

#### Doing the Investigation

Have students share both their solution and how they found it.