HCF − Highest Common Factor or Greatest Common Factor
It is simply the greatest of the common factors
- Example 1. What is the highest common factor of 12 and 30?
The factors of 12 are 1, 2, 3, 4, 6 and 12
The factors of 30 are 1, 2, 3, 5, 6, 10, 15 and 30
So the highest common factor of 12 and 30 is 6
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