The document provides instruction on using divisibility rules for 2, 5, and 10 to find common factors of numbers. It gives the rules for determining if a number is divisible by 2 (even or ends in 0, 2, 4, 6, or 8), 5 (ends in 0 or 5), or 10 (ends in 0). Examples are provided. Students are asked to use the rules to identify factors and common factors of various number pairs.
1. Math 5
Week 1 Day 1
Uses divisibility rules for 2, 5, and 10 to find
the common factors of numbers.
2. Directions: Identify whether the given
number is divisible by 2, 5 or 10. Do
this in your answer sheet.
1) 18 _____
2) 125 _____
3) 30 _____
4) 344 _____
5) 650 _____ T
3. When is a number divisible
by 2?
(A number is divisible by 2
if it is even, or ends in 0, 2,
4, 6 or 8.)
T
4. Why is 20 is divisible by 2?
(20 is an even number
because it ends in 0.) So, 20
is divisible by 2.
T
5. How do we know if a
number is divisible by 2,
5 or 10?
T
6. Divisibility Rule for 2
A number is divisible by 2 if the
ones digit of the number is 0,
2, 4, 6 or 8.
Example 1: 436 is divisible by 2
because its ones digit is 6.
T
7. Divisibility Rule for 5
A number is divisible by 5 if the
ones digit of the number is 0 or
5.
Example 2: 225 is divisible by 5
because its ones digit is 5.
T
8. Divisibility Rule for 10
A number is divisible by 10 if the
ones digit of the number is 0.
Example 3: 720 is divisible by 10
because the ones digit is 0.
Now, using the divisibility rules for
2, 5 and 10, let us find the common
factors of 20 and 40 T
9. GROUP I
Identify mentally whether or
not each larger number is
divisible by the
smaller number. Write “Yes” if
the number is divisible, and
“No” if it is not.
G
10. 1) Is 130 divisible by 2?
2) Is 326 divisible by 5?
3) Is 124 divisible by 2?
4) Is 405 divisible by 5?
5) Is 567 divisible by 2?
G
11. GROUP II
Use the divisibility rules for 2, 5
and 10 to list down all the
factors of each pair of numbers.
Then, encircle the common
factors.
G
12. 1) 15 and 45
2) 26 and 18
3) 50 and 80
4) 32 and 12
5) 54 and 60
2. Group reporting G
13. Directions: Using the
divisibility rules for 2, 5, and
10, fill in the missing factors.
Then, find the common
factors.
a) 30 : 1, 2, 3, __, __,10,15,30
20 : 1, 2, 4, __, __, 20
Common Factors: __________ I
14. b) 36 : 1, 2, 3, __,6, __, __,
18, 36
12 : 1, 2, 3, __, __, 12
Common Factors: __________
I
15. c) 48 : 1, 2, 3, 4, __, __,12,16,
__, 48
24 : 1, 2, 3, 4, 6, __, __, __.
Common Factors: __________
I
17. Directions: Choose the letter of the
correct answer.
1) Which of the following is the set
of common factors of 48 and 60?
A. 1, 2, 3, 4, 6, 12
B. 1, 2, 3, 4, 8, 12
C. 1, 2, 3, 4, 6, 8
D. 1, 2, 4, 6, 12
A
18. 2) 1, 2, 5, and 10 are
the common factors of
____
A.20 and 25
B.20 and 30
C. 25 and 30
D. 15 and 25 A
19. 3) One of the following
is NOT a factor of 32?
A. 2
B. 4
C. 6
D. 8
A
20. 4) Which of the numbers below
is divisible by both 5 and 10?
A. 75 C. 235
B. 105 D. 540
5) 124 is divisible by _____.
A.2 C. 6
B.5 D. 10
A
