Method 1:
List the factors of each number.
Factors of 12: 2, 3, 4, 6, 12
Factors of 30: 2, 3, 5, 6, 10, 15, 30
Identify the greatest common factor.
The greatest common factor of 12 and 30 is 6.
Method 2:
Write the prime factorization of each number.
12 = 3 × 2 × 2.
30 = 3 × 2 × 5.
The GCF is the product of the common prime factors in each number.
GCF = 3 × 2.
The greatest common factor of 12 and 30 is 6.
The greatest common factor of 12 and 30 is 6.
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