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What is the Greatest Common Factor of 4 and 18?

Greatest common factor (GCF) of 4 and 18 is 2.

GCF(4,18) = 2

We will now calculate the prime factors of 4 and 18, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 4 and 18.

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How to find the GCF of 4 and 18?

We will first find the prime factorization of 4 and 18. After we will calculate the factors of 4 and 18 and find the biggest common factor number .

Step-1: Prime Factorization of 4

Prime factors of 4 are 2. Prime factorization of 4 in exponential form is:

4 = 22

Step-2: Prime Factorization of 18

Prime factors of 18 are 2, 3. Prime factorization of 18 in exponential form is:

18 = 21 × 32

Step-3: Factors of 4

List of positive integer factors of 4 that divides 4 without a remainder.

1, 2

Step-4: Factors of 18

List of positive integer factors of 18 that divides 4 without a remainder.

1, 2, 3, 6, 9

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 4 and 18. The biggest common factor number is the GCF number.
So the greatest common factor 4 and 18 is 2.

Also check out the Least Common Multiple of 4 and 18