Finding Greatest Common Factor

GCF of 20 and 80

• 10

• 20

• 5

• 40

• Not Given

Sara had 16 red flowers and 24 yellow flowers. She wants to make bouquets with the same number of each color flower in each bouquet. What is the greatest number of bouquets that she can make?

Hint: Find the GCF

• 4

• 2

• 48

• 8

List the factors of 12 & 20, then identify the greatest common factor.
12-
20-
GCF=

• 12- 1, 2, 5, 7  20-10, 20, 30, 40 GCF 10

• 12-1, 12, 24, 36  20-20, 40, 60, 80 GCF 40

• 12-2, 4, 6   20-1, 10, 20 GCF 20

• 12-1, 2, 3, 4, 6, 12  20-1, 2, 4,5,10, 20 GCF 4

What is the GCF of 12 and 18?

• 3

• 4

• 6

• 2

What is the GCF of 32 and 40?

• 2

• 4

• 6

• 8

What is the GCF of 4 and 6?

• 2

• 3

• 4

• 6

What is the GCF 24 and 36?

• 8

• 6

• 12

• 4

Find the GCF of 44 and 99

Find the GCF of 4 and 12

Find the GCF of 16 and 36