IDENTIFYING THE FACTORS OF A NUMBER 5

1. IDENTIFYING THE
FACTORS OF A
NUMBER

2. QUESTIONS:
• What did the pupils want
to give to their mothers?
• Why did the pupils want to
give roses to their
mothers?
• How many boxes of roses
should they order?

3. FACTORS
Are expressed
as the product
of two whole
numbers.

4. LISTING METHOD
You will list all the
factors of a given
number.

5. EXAMPLE:
WHAT IS THE FACTORS OF 12?
1×12 2×6 3×4
THE FACTORS OF 12 ARE:
1, 2, 3, 4, 6, 12.

6. EXAMPLE:
WHAT IS THE FACTORS OF 20?
1×20 2×10 4×5
THE FACTORS OF 20 ARE:
1, 2, 4, 5, 10,

7. EXAMPLE:
WHAT IS THE FACTORS OF 30?
1×30 2×15 3×10
THE FACTORS OF 30 ARE:
1, 2, 3, 5, 6, 10, 15, 30.
5×6

8. DIVISIBILITY
A whole number
is divisible by
any of its factors.

9. EX AMPLE:
IS12 DIVISIBLE BY 2, 3, AND 6?
12÷2
THEREFORE 12 IS DIVISIBLE
BY: 2, 3, 6.
12÷3
12÷6
= 4
= 6 = 2

10. DIVISIBLE BY 2
The last
number should
be even.

11. EX AMPLE:
12
134
68
566

12. DIVISIBLE BY 3
The sum of the
digits should be
divisible by 3.

13. EX AMPLE:
1,461 1+4+6+
1
=
=
9
324 = 3+2+
4=
12

14. DIVISIBLE BY 4
The last two
digits should be
divisible by 4.

15. EX AMPLE:
248 48 ÷ 4=
=
6
3,124 =24 ÷
4=
12

16. QUIZ
1. 318 =
2. 2,236=
3. 124 =
4. 117 =
5. 416=
6. 537

17. DIVISIBLE BY 5
The last digit
should be 0
or 5.

18. EX AMPLE:
570 570 ÷ 5=
=
427
2,135 =2,135 ÷ 5
=
114

19. DIVISIBLE BY 6
The number
should be divisible
by 2 and 3.

20. EX AMPLE:
1,461 1+4+6+
1
=
=
324
12

21. QUIZ
1. 942
=2. 726
=3. 230 =
4. 1,905 =
5. 2,712
=6. 3,405

23. DIVISIBLE BY 7
Multiply the last
digit by 2. Subtract
it from the rest of
the numbers.

24. EX AMPLE:
882 2 × 2 =
4
=
=
12
88 – 4
84 ÷
7
8
4=
882 ÷ =126

25. DIVISIBLE BY 8
The last three
digits should be
divisible by 8.

26. EX AMPLE:
2,848 848 ÷
8
= =
=
=
174
106
1,392
1,392
2,848 =356
392 ÷
8
=49

27. DIVISIBLE BY 9
The sum of the
digits should be
divisible by 9.

28. EX AMPLE:
2,367 2+3+6+
7
=
=
=26
18
2,367 ÷ 9
18 ÷ 9 =2

29. QUIZ
1. 1,648
=2. 4,779
=3. 224 =
4. 917 =
5. 1,416
=6. 2,538

31. DIVISIBLE BY 10
The last digit
should be
zero.

32. EX AMPLE:
470 470 ÷ 10=
=
313
3,130 =3,130 ÷ 10
=
47

33. DIVISIBLE BY 11
The difference of
the sum of the
alternating digits
is 0 or 11.

34. EX AMPLE:
9,273 ÷ 11
(9+7)–(2+3)=
=
=84
1116-5
9,273

35. DIVISIBLE BY 12
The number is
divisible by
both 3 and 4.

36. EX AMPLE:
1,428 1+4+2+
8
=
=515÷3
1,428÷3 =476

37. EX AMPLE:
1,428 28÷4= =7
1,428÷4 =357
1,428÷12 =119