Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

Monthly Update sign up
Mailing List signup
Search
MENU
Learning Math Home
Number and Operations Session 5, Part B: Divisibility Tests
 
Session5 Part A Part B Part C Homework
 
Glossary
number Site Map
Session 5 Materials:
Notes
Solutions
Video

Session 5, Part B:
Divisibility Test (50 minutes)

In This Part: Developing Testing Rules | Divisibility Tests for 2, 5, and 10
Divisibility Tests for 3 and 9 | Divisibility Tests for 4 and 8 | Divisibility Test for 11

Another way to examine the characteristics of base ten numbers is to look at the patterns that emerge when we try to determine whether a particular number is evenly divisible by another number. Note 2

Use the following numbers for Problems B1 and B2. Remember, we are only looking for patterns here. The actual divisibility rules will be explored in the following sections.

Row

Numbers

1

1

11

21

31

151

2461

2

2

12

22

32

152

2462

3

3

13

23

33

153

2463

4

4

14

24

34

154

2464

5

5

15

25

35

155

2465

6

6

16

26

36

156

2466

7

7

17

27

37

157

2467

8

8

18

28

38

158

2468

9

9

19

29

39

159

2469

10

10

20

30

40

160

2470

Problem B1

Solution  

a. 

Which of the above numbers are divisible by 2?


Stop!  Do the above problem before you proceed.  Use the tip text to help you solve the problem if you get stuck.
Look across the rows of numbers. Do you see any patterns?   Close Tip

 
 

b. 

Which of the above numbers are divisible by 5?

c. 

Which of the above numbers are divisible by 10?

d. 

What is the test for divisibility by 2, 5, or 10?


Stop!  Do the above problem before you proceed.  Use the tip text to help you solve the problem if you get stuck.
Which digits of the number must you examine to test for divisibility by 2, 5, or 10? Why?   Close Tip

 

Problem B2

Solution  

a. 

Which of the above numbers are divisible by 9?


Stop!  Do the above problem before you proceed.  Use the tip text to help you solve the problem if you get stuck.
Look across the rows or columns of numbers. Do you see any patterns?   Close Tip

 
 

b. 

Which of the above numbers are divisible by 3?

c. 

What is the test for divisibility by 9 or 3?


Next > Part B (Continued): Divisibility Tests for 2, 5, and 10

Learning Math Home | Number Home | Glossary | Map | ©

Session 5: Index | Notes | Solutions | Video

Home | Catalog | About Us | Search | Contact Us | Site Map

  • Follow The Annenberg Learner on Facebook

© Annenberg Foundation 2013. All rights reserved. Privacy Policy