The factors of are 12, 6, 4, 3, 2, 1, while those for 20 are 20, 10, 5, 4, 2, 1. The common highest factor for the two numbers is 4.
The highest common factor (HCF) of 12 and 20 is 4. This is found by identifying the factors of both numbers and selecting the largest one that they share. Thus, the HCF is 4.
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