The factors of 40 are 1, 2, 4, 5, 8, 10, 20, and 40 .
The factors of 48 are 1, 2, 3, 4, 6, 8, 12, 16, 24, and 48 .
The factors that are common to 40 and 48 are 1, 2, 4, and 8 .
The greatest one is 8 .
The greatest common factor (GCF) of 40 and 48 is 8. This is found by identifying the common factors of both numbers. The common factors are 1, 2, 4, and 8, with 8 being the largest.
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