1. Divisibility
Rules!

2. What is Divisibility?
Divisibility means that after dividing, there will be no remainders. The divisor can evenly divide into the dividend.

3. 356,821 The divisibility rules can help you!
Can you tell by just looking at this number if it is divisible by 2?
by 3?
by 4?
by 5?
by 6 ?
by 9?
By 10?
The divisibility rules can help you!

4. Divisibility rules help you learn shortcuts to tell when a number can be divided by another number without any remainders.

5. Divisibility by 2 18 ÷ 2 = 9 A number is divisible by 2
if the number is even.
18 ÷ 2 = 9
22 ÷ 2 = 11
(18 and 22: Notice that both of these dividends are even.)
21 ÷ 2 = 10 R1
(21: not an even number.)

6. Are these numbers divisible by 2?
Now You Try
Are these numbers divisible by 2?
79,458
1,279
6,249
51,553
19,050
35,792

7. Divisibility by 3
A number is divisible by 3 if the sum of the digits is divisible by 3.
Is the number 135 divisible by 3?
Add the digits: = 9
Yes, 135 is divisible by 3 because the sum of the digits is divisible by 3.

8. For example, take the number 738
Dividing by 3
For example, take the number 738
Add up the digits of the number 7 + 3 8 = 18
Is 18 divisible by 3?
If that number is divisible by 3, then the original number is
Oh yeah!
If your sum is still a big number, continue to add the digits
1 + 8 = 9
Is 9 divisible by 3?

9. Are these numbers divisible by 3?
Now You Try
Are these numbers divisible by 3?
639 56 86
360
468
2,511

10. If the last 2 digits together are divisible by 4
Dividing by 4
If the last 2 digits together are divisible by 4
Example: 72,624
Is 24 divisible by 4?
Great scott

11. Are these numbers divisible by 4?
Now You Try
Are these numbers divisible by 4?
97,584
123,261
48,156
53,920
25,767
13,224

12. Divisibility by 5
A number is divisible by 5 if it ends in 0 or 5.
25 ÷ 5 = 5
23 ÷ 5 = 4 R3

13. Are these numbers divisible by 5?
Now You Try
Are these numbers divisible by 5?
198,554
6,890
31,345
68,902
371,845
20,001

14. Divisibility by 6 A number is divisible by 6
if it is divisible by both 2 AND 3.
Is 42 divisible by 6?
Think:
Is 42 divisible by 2?
Is 42 divisible by 3?
Is 51 divisible by 6?
Hint: Is it an even number?

15. Are these numbers divisible by 6?
Now You Try
Are these numbers divisible by 6?
897
258
630
345 84
8,235

16. Divisibility by
A number is divisible by 9 if the sum of its digits is divisible by 9.
369 is divisible by 9
because
=18
1 + 8 = 9
and
9 is divisible by 9.

17. Dividing by 9 Add up the digits of the number 27 9 + 2 4 6 5 1 =
For example, take the number 924,561
Add up the digits of the number 27 9 + 2 4 6 5 1 =
Is 27 divisible by 9?
If that number is divisible by 3, then the original number is
Oh yeah!
If your sum is still a big number, continue to add the digits
2 + 7 = 9
Is 9 divisible by 9?

18. Are these numbers divisible by 9?
Now You Try
Are these numbers divisible by 9?
55,578
22,398
91,548
17,903
32,490
83,402

19. Divisibility by A number is divisible by 10 if it ends in 0.
30 ÷ 10 = 3
340 ÷ 10 = 34
67 ÷ 10 = 6 R7
784 ÷ 10 =78 R4

20. Are these numbers divisible by 10?
Now You Try
Are these numbers divisible by 10?
24,578
39,800
48,003
19,030
490,870
65,432

21. Is it divisible by: 2 3 4 5 6 9 10
444,555,448
26,350
74,673,042
61,616,168
732,510
9,623,205

22. Is it divisible by: 2 3 4 5 6 9 10
123,456,789
58,468,240
52,301,042
246,813,579
135,790,135
813,423,700

23. After all, divisibility rules!

24. THE END