Math Investigations

Help with Opening PDF Files

Chapter 8

Part 1: For the activity in the Teacher's Edition, page 204

Provide students with a copy of the Problem Worksheet (PDF file).

Some students may need to use counters to solve this problem.

Answer: One row of 12, two rows of six, three rows of four, six rows of two, 12 rows of one.

Part 2: Be an Investigator

Materials

  • A good time to do this investigation is after Lesson 2 on arrays and multiplication.

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 two to four to work on the investigation.

Doing the Investigation

The students can use counters that they pretend are stamps to help them solve the problem presented in this investigation. As you observe the students, make sure they are putting the counters into arrays. The students should discover that they cannot find arrays for 10, 11, 13, 14, 17, 19, 22, and 23 that meet all of Teva's rules for the page layout.

Answers:

12 stamps on a page
3 rows with 4 stamps in a row or
4 rows with 3 stamps in a row

15 stamps on a page
3 rows with 5 stamps in a row or
5 rows with 3 stamps in a row

16 stamps on a page
4 rows with 4 stamps in a row

18 stamps on a page
3 rows with 6 stamps in a row or
6 rows with 3 stamps in a row

20 stamps on a page
4 rows with 5 stamps in a row or
5 rows with 4 stamps in a row

21 stamps on a page
3 rows with 7 stamps in a row or
7 rows with 3 stamps in a row

24 stamps on a page
3 rows with 8 stamps in a row or
8 rows with 3 stamps in a row or
6 rows with 4 stamps in a row or
4 rows with 6 stamps in a row


Houghton Mifflin Math Grade 3