This document provides information about divisibility rules. It defines prime and composite numbers. It lists the divisibility rules for numbers 2 through 10. Numbers are divisible by 2 if the last digit is even, by 3 if the sum of the digits is divisible by 3, by 4 if the last two digits form a number divisible by 4, and so on. It then provides examples of numbers that are and are not divisible based on these rules. Prime numbers in the list from 1 to 50 are highlighted. Finally, specific numbers are identified as being divisible or not by numbers 2 through 10 according to the rules.

1. Name ________________________________ Date _________________
Mrs. Labuski / Mrs. Portsmore Per ________ Unit 4 Lesson 1 Divisibility Rules
TB 4-1
Essential Question: Why do we represent numbers in different ways?
VOCABULARY DEFINTION EXAMPLE
Prime Number
Composite Number
Divisible
Highlight or circle all of the Prime Numbers:
1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40
41 42 43 44 45 46 47 48 49 50

2. Divisibility Rules
A number is divisible by: Divisible Not Divisible
2 if the last digit is even. (0,2,4,6,8) 3,978 4,975
315 139
3 if the sum of the digits is divisible by 3.
(3+1+5 =9) (1+3+9=13)
4 if the last two digits form a number that is divisible by
8,512 7,518
4.
5 if the last digit is 0 or 5. 17,975 10,978
48 20
6 if the number is divisible by both 2 and 3 evenly. (48÷2=24 (20÷2=10
48÷3=16) 20÷3≠6.666)
711 93
9 if the sum of the digits is divisible by 9.
(7+1+1=9) (9+3=12)
10 if the last digit is 0. 15,990 10,536
divisible by both 2 and
if the last digit is 0 or 5
if the sum of the digits
if the last digit is even
if the sum of the digits
form a number that is
if the last digit is 0
if the last two digits
if the number is
is divisible by 9
is divisible by 3
divisible by 4
3
Number 2 3 4 5 6 9 10
32
81
45
56
72

3. 21
540
Name ________________________________ Date _________________
Mrs. Labuski / Mrs. Portsmore Per ________ Unit 4 Lesson 1 Divisibility Rules
TB 4-1
Essential Question: Why do we represent numbers in different ways?
VOCABULARY DEFINTION EXAMPLE
A number that is 2 (1,2)
Prime Number divisible by only the 3 (1,3)
numbers 1 and itself. 5 (1,5)
A number that is 4(1,4,2)
Composite
divisible by more than 6 (1,6,2,3)
Number
two numbers 8 (1,8,2,4)
A number is divisible by
another number if the 42 ÷ 6 = 7
Divisible quotient is a whole 42 is divisible by 6
number with no
remainder.
Highlight or circle all of the Prime Numbers:
1 2 3 4 5 6 7 8 9 10
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40

4. 41 42 43 44 45 46 47 48 49 50
Divisibility Rules
A number is divisible by: Divisible Not Divisible
2 if the last digit is even. (0,2,4,6,8) 3,978 4,975
315 139
3 if the sum of the digits is divisible by 3.
(3+1+5 =9) (1+3+9=13)
4 if the last two digits form a number that is divisible by
8,512 7,518
4.
5 if the last digit is 0 or 5. 17,975 10,978
48 20
6 if the number is divisible by both 2 and 3 evenly. (48÷2=24 (20÷2=10
48÷3=16) 20÷3≠6.666)
711 93
9 if the sum of the digits is divisible by 9.
(7+1+1=9) (9+3=12)
10 if the last digit is 0. 15,990
divisible by both 2 and 10,536
if the last digit is 0 or 5
if the sum of the digits
if the last digit is even
if the sum of the digits
form a number that is
if the last digit is 0
if the last two digits
if the number is
is divisible by 9
is divisible by 3
divisible by 4
3
Number 2 3 4 5 6 9 10
32  
81  
45   
56  

5. 72     
21 
540       