Calculate the Greatest Common Factor or GCF of 420

The instructions to find the GCF of 420 are the next:

1. Decompose all numbers into prime factors

2. Write all numbers as the product of its prime factors

3. Choose the common prime factors with the lowest exponent

Common prime factors: 2 , 3 , 5 , 7

Common prime factors with the lowest exponent: 2², 3¹, 5¹, 7¹

4. Calculate the Greatest Common Factor or GCF

Remember, to find the GCF of several numbers you must multiply the common prime factors with the lowest exponent.

GCF = 2². 3¹. 5¹. 7¹ = 420

Also calculates the:

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