Answer :
To find the greatest common factor (GCF) of the numbers 42, 126, and 210, follow these steps:
1. List the Factors:
- Factors of 42 are: 1, 2, 3, 6, 7, 14, 21, 42
- Factors of 126 are: 1, 2, 3, 6, 7, 9, 14, 18, 21, 42, 63, 126
- Factors of 210 are: 1, 2, 3, 5, 6, 7, 10, 14, 15, 21, 30, 42, 70, 105, 210
2. Identify Common Factors: Find the factors that appear in all three lists:
- Common factors are: 1, 2, 3, 6, 7, 14, 21, 42
3. Select the Greatest Common Factor:
- The largest number in the list of common factors is 42.
Therefore, the greatest common factor of 42, 126, and 210 is 42.
1. List the Factors:
- Factors of 42 are: 1, 2, 3, 6, 7, 14, 21, 42
- Factors of 126 are: 1, 2, 3, 6, 7, 9, 14, 18, 21, 42, 63, 126
- Factors of 210 are: 1, 2, 3, 5, 6, 7, 10, 14, 15, 21, 30, 42, 70, 105, 210
2. Identify Common Factors: Find the factors that appear in all three lists:
- Common factors are: 1, 2, 3, 6, 7, 14, 21, 42
3. Select the Greatest Common Factor:
- The largest number in the list of common factors is 42.
Therefore, the greatest common factor of 42, 126, and 210 is 42.