What is the GCF of 25 and 45?
Understand the Problem
The question is asking for the greatest common factor (GCF) of the numbers 25 and 45. To solve this, we will identify the factors of both numbers and determine the largest factor that they have in common.
Answer
5
Answer for screen readers
The greatest common factor (GCF) of 25 and 45 is 5.
Steps to Solve
- Identify the factors of 25
The factors of 25 are the numbers that can multiply together to give 25. They are: 1, 5, 25.
- Identify the factors of 45
The factors of 45 are the numbers that can multiply together to give 45. They are: 1, 3, 5, 9, 15, 45.
- List the common factors
Now, we will list the factors from both numbers to find the common ones:
- Factors of 25: 1, 5, 25
- Factors of 45: 1, 3, 5, 9, 15, 45
The common factors are 1 and 5.
- Determine the greatest common factor
From the common factors, the greatest is 5.
The greatest common factor (GCF) of 25 and 45 is 5.
More Information
The GCF is useful in simplifying fractions, finding common denominators, and solving problems involving ratios. Interestingly, prime factorization can also be used to find the GCF.
Tips
- Forgetting to list all factors correctly. Always double-check your factors.
- Misidentifying the GCF by picking the largest number instead of the largest common factor.
