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Multiplication
Division
Divisibility Rules
Pg. 3
Pg. 4
Pg. 5
“Divisible by” means:
It goes into the other
number without a remainder!
Examples:
12 ÷ 6 = 2
15 ÷ 5 = 3
Number: 2
A number is divisible by 2 if the
digit is even.
Examples:
last
(0, 2, 4, 6, 8)
8
7
0
347
Now You Try:
IS NOT divisible by 2?
572 1464 249
Which number
Need More Practice: Numbers Divisible by 2
Number: 3
*Hint add the digits and see if you
can divide that number by 3
Examples:
7 + 5 = 12
75
12 ÷ 3 = 4
Number: 5
A number is divisible by 5 if the
digit is a
0 or 5.
Examples:
5
1480
61
ends in a 5
ends on a 0
last
Now You Try:
Which number IS NOT divisible
by 5?
9820
779
560
Number:10
A number is divisible by 10 is if it ends in a
ZERO
.
Example:
0
ends in a zero
0
ends in a zero
763
41
Now You Try:
Find the number that
56,920
IS NOT
7537
divisible by ten.
870
Number: 4
A number is divisible by 4 if the
last two digits are divisible by 4.
Examples:
13
6
20
72
20 ÷ 4 = 5
72 ÷ 4 = 18
Now You Try:
Which number
IS NOT divisible by 4?
524 4101
116
Need More Practice: Numbers Divisible by 4
Number: 6
A number is divisible by 6 when it is
2 AND 3.
Examples:
divisible by
408 ends in an even number (2 rule)
sum of the digits is divisible by 3
Now You Try:
Which number IS NOT divisible by 6?
8700
523
7602
Number: 9
A number is divisible by 9 if the sum of
the digits is divisible by 9.
Example:
963
9 + 6 + 3 = 18
18 ÷ 9 = 2
Number Theory
What does that mean?
What is an even number?
• Can be divided by 2
• Unit digit is 0, 2, 4, 6, or 8
• Is a multiple of 2
• 782,444
•4
• 608
What is an odd number?
•Cannot be divided by 2
•Unit digit is 1, 3, 5, 7, or 9
•Is not a multiple of 2
•782,333
•5
•607
EVEN + EVEN = ?
12 + 4
ODD + ODD = ?
11+9
EVEN + ODD = ?
8+7
Number Theory…