Frequently Asked Questions
Q: What are some ways to identify factors?
A: You can make arrays or use a factor rainbow.
For example, identify all the factors of 12.
The number of rows and number of columns in an
array represent factors of 12.
1-by-12
1, 2, 3, 4, 6, and 12 are factors of 12.
2-by-6
3-by-4
The rainbow connects one factor
of 12 to the number you multiply
it by to get 12.
1 2 3
4 6 12
Q: What are some ways to identify multiples?
A: You can use addition or multiplication to identify
multiples.
For example,
you can multiply
5 by the counting
numbers or you
can skip count
by 5s to identify
multiples of 5.
Multiples of 5
Multiply 5 by
Product
+5
0
+5
5
1 2 3 4 5
5 10 15 20 25
+5
10
+5
15
+5
20
25
Q: How are prime and composite numbers different?
A: Prime numbers have only two different factors: 1 and
the number itself. Composite numbers have more than
two different factors. The numbers 0 and 1 are
considered to be neither prime nor composite.
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NEL
Practice
Lesson 1
Reading Strategy
1. A veterinarian has 40 indoor dog kennels.
a) What arrays can she form with 40 kennels?
b) How can you use the arrays in part a) to identify
all the factors of 40?
Monitoring
Comprehension
List the math words
on this page. How
well do you
understand these
words? What do you
know about them?
2. Identify the factors of each number.
a) 14
b) 45
c) 54
d) 75
Lesson 2
3. The Women’s World Cup soccer tournament is held
every four years. The World Cup was played in China
in 2007. In what years will the five World Cups after
China be played?
4. Identify the first five multiples of each number.
Explain what you did for one number.
a) 11
b) 22
c) 20
d) 35
Lesson 3
5. You can form a two-digit
number by spinning the spinner
twice. The first number spun is
the tens digit. The second
number spun is the ones digit.
How many more composite
numbers than prime numbers
can be spun?
2
5
3
4
Lesson 4
48
6. What factors of 48 can you identify from the factor
tree at the left?
2
24
3
NEL
8
7. Pablo found that his uncle’s age can be divided by
three different prime numbers. What are three
possible ages of his uncle? Show your work.
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