Factors
What is a factor?
A FACTOR is a number that you multiply with another number to get the product.
What is the GCF?
The Greatest common factor is the biggest factor (number) from two given products. The biggest number of the common factors.
What is a composite number?
A prime number has 1 set of factors - 1 x itself.
A composite number has more than one factor pair. (many factors)
What are multiples?
A multiple is the product of a whole number times another whole number.
What is the LCM?
The LCM is the least common multiple. It is the smallest common number when comparing multiples.
Find the factors of 25.
1, 5, 25
What is the GCF of 12 and 20?
GCF = 4
Factors of 12 - 1, 2, 3, 4, 6, 12
Factors of 20 - 1, 2, 4, 5, 10, 20
Common factors - 1, 2, 4
Is the number prime or composite? Why?
2
prime - it only has 1 x 2 - only 1 factor pair.
Find the first 10 multiples of 2.
2, 4, 6, 8, 10, 12, 14, 16, 18, 20
What is the LCM of the numbers 6 and 8?
LCM = 24
Multiples of 6 - 6, 12, 18, 24, 30, 36, 42, 48
Multiples of 8 - 8, 16, 24...don't have to go any further ...lcm is 24.
Find the factors of 40.
1, 2, 4, 5, 8, 10 ,20 , 40
What is the GCF of 10 and 15?
Factors of 10 - 1, 2, 5, 10
Factors of 15 - 1, 3, 5, 15c
Common factors - 1, 5
Is the number prime or composite? Why?
4
Composite. It has 1, 2, 4 as factors. Many factors.
Is 99 a multiple of 3? Why or why not?
Yes because 3 can go into 99, 33 times.
What is the LCM of 5 and 10?
LCM = 10
Multiples of 5 - 5, 10, 15, 20,
Multiples of 10 - 10, 20, 30
Is 5 a factor of 36?
No-5 will always have a 0 or 5 in the product.
Factors of 36 are:
1, 2, 3, 4, 6, 9, 12, 18, 36
What is the GCF of 24 and 30?
Factors of 24 - 1, 2, 3, 4, 6, 8, 12, 24
Factors of 30 - 1, 2, 3, 5, 6, 10, 15, 30
Common factors - 1, 2, 3, 6
Is the number prime or composite? Why?
20
Composite - has many factors
Find the first 8 multiples of 9.
9, 18, 27, 36, 45, 54, 63, 72,
What is the LCM of 3 and 9?
LCM = 9
Multiples of 3 - 3, 6, 9, 12, 15
Multiples of 9 - 9, 18, 27, 36, 45
Find the factors of 48. Is 10 a factor of 48?
No- 10 will always have a product with a 0.
1, 2, 3, 4, 6, 8, 12, 16, 24, 48
What is the GCF of 25 and 45?
Factors of 25 - 1, 5, 25
Factors of 45 - 1, 3, 5, 9, 15, 45
Common factors - 1, 5
Is the number prime or composite?
11
Is 81 a multiple of 8? Why or why not?
No because if you do the multiples of 8, you won't find 81.
8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88
What is the LCM of 12 and 20?
LCM = 60
Multiples of 12 - 12, 24, 36, 48, 60, 72, 84, 96
Multiples of 20 - 20, 40, 60