Review - LCM and GCF

GREATEST COMMON FACTOR

REVIEW LESSON IN MATHEMATICS 8

​GREATEST COMMON FACTOR

​The highest number that divides exactly into two or more numbers.

Steps in Finding the Greatest Common Factor

• ​Step 1 - Find all the factors of each number.

• ​Step 2 - Get the common factors.

• ​Step 3 - Choose the greatest common factor.

​Find the GCF of 12 and 16.

• ​12 - 1, 2, 3, 4, 6, 12

• ​16 - 1, 2, 4, 8, 16

​Find the GCF of 12 and 30.

• ​12 - 1, 2, 3, 4, 6, 12

• ​30 - 1, 2, 3, 5, 6, 10, 15, 30

​Find the GCF of 12 and 30.

• ​24 - 1, 2, 3, 4, 6, 12, 24

• ​108 - 1, 2, 3, 4, 6, 9, 12, 18, 27, 36, 54, 108

Fill in the Blank

The GCF of 33 and 22 is ______.

Fill in the Blank

The GCF of 30 and 20 is _____.

Fill in the Blank

The GCF of 27 and 33 is _____.

Fill in the Blank

The GCF of 32 and 48 is _____.

Fill in the Blank

The GCF of 42, 28, and 56 is _____.