what are the greatest common factors of 8 and 12
What are the greatest common factors of 8 and 12?
Answer: The greatest common factor (GCF) of two or more numbers is the largest number that divides all of them without leaving a remainder. To find the GCF of 8 and 12, we can use two methods: the prime factorization method and the Euclidean algorithm. Let’s explore both approaches for clarity.
1. Prime Factorization Method
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Prime Factorization of 8:
8 = 2^3 -
Prime Factorization of 12:
12 = 2^2 \times 3 -
Identify the Common Prime Factors: The common prime factor of 8 and 12 is (2).
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Multiply Common Prime Factors with the Lowest Exponents:
- The lowest exponent of (2) in both prime factorizations is (2).
\text{GCF} = 2^2 = 4
Thus, the greatest common factor of 8 and 12 is 4.
2. Euclidean Algorithm
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Use the Euclidean Algorithm to find the GCF by repeatedly applying the formula:
\text{GCF}(a, b) = \text{GCF}(b, a \mod b)where (a) and (b) are the given numbers.
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Step-by-Step Approach:
- Start with (a = 12) and (b = 8).
- Calculate (12 \mod 8):12 \mod 8 = 4
- Now, apply the Euclidean Algorithm with (b = 8) and the result (4):\text{GCF}(8, 4) = 8 \mod 4 = 0
- Since the remainder is 0, the GCF is the non-zero divisor, which is 4.
Thus, using both methods, the greatest common factor of 8 and 12 is confirmed to be 4.