Find the greatest common factor (GCF)

Example 1:
Find the greatest common factor for 36 and 56.
Solution:
36 = 1 × 36, 2 × 18, 3 × 12, 4 × 9, 6 × 6.
56 = 1 × 56, 2 × 28, 4 × 14, 7 × 8.
The common factors of 36 and 56 are 1, 2, 4.
The greatest common factor of 36 and 56 is 4.
Example 2:
Find the greatest common factor of 18 and 24.
Solution:
18 = 1 × 18, 2 × 9, 3 × 6.
24 = 1 × 24, 2 × 12, 3 × 8, 4 × 6.
The common factors of 18 and 24 are 1, 2, 3, 6.
The greatest common factor of 18 and 24 is 6.
Note:
Using the greatest common factor (GCF) to simplyfy fractions.
Both numerator and denominator of a fraction divide by the greatest common factor (GCF) to get a simplest form of a fraction.