The greatest common factor (GCF) of 7 and 42 is 7. The GCF is the largest number that divides both numbers without leaving a remainder. To find the GCF of 7 and 42, we can list the factors of each number:
- Factors of 7: 1, 7
- Factors of 42: 1, 2, 3, 6, 7, 14, 21, 42
The common factors of 7 and 42 are 1 and 7. Since 7 is the largest of these, it is the greatest common factor.
Another method to find the GCF is by using prime factorization:
- Prime factors of 7: 7
- Prime factors of 42: 2 × 3 × 7
The common prime factor is 7, so the GCF is 7.