Greatest common factor explained | Factors and multiples | Pre-Algebra | Khan Academy

What is the greatest common factor (GCF) of 12 and 8?

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What is the greatest common divisor (GCD) of 25 and 20?

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Two numbers are called "relatively prime" if their greatest common factor is 1. Which pair of numbers is relatively prime?

• (12, 8)

• (25, 20)

• (5, 12)

• (6, 12)

Find the greatest common factor (GCF) of 6 and 12.

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