The question "What is the greatest common divisor Class 5?" is unclear. It seems to be missing information. A better phrasing would be: "What is the greatest common divisor (GCD) of numbers typically encountered in a Class 5 curriculum?", or "How is the greatest common divisor (GCD) taught in Class 5?". Because the question is not precisely defined, I will address the concept of the greatest common divisor (GCD) as it might be introduced at the Class 5 level, alongside examples appropriate for that grade.
Understanding the Greatest Common Divisor (GCD)
The greatest common divisor (GCD), also known as the highest common factor (HCF), is the greatest common factor number that divides them, exactly. This means it's the largest number that can divide two or more numbers without leaving a remainder. The reference text highlights this basic definition. For example, the GCD of 15 and 10 is 5 because 5 is the largest number that divides both 15 and 10.
GCD in Class 5: Examples and Methods
In Class 5, students are usually introduced to the concept of GCD using smaller numbers and simpler methods. Here are some examples and a common method:
Example 1: Finding the GCD of 12 and 18
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List the factors of each number:
- Factors of 12: 1, 2, 3, 4, 6, 12
- Factors of 18: 1, 2, 3, 6, 9, 18
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Identify the common factors: 1, 2, 3, 6
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Determine the greatest common factor: 6
Therefore, the GCD of 12 and 18 is 6.
Example 2: Finding the GCD of 15 and 25
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List the factors of each number:
- Factors of 15: 1, 3, 5, 15
- Factors of 25: 1, 5, 25
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Identify the common factors: 1, 5
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Determine the greatest common factor: 5
Therefore, the GCD of 15 and 25 is 5.
Method: Listing Factors
The examples above demonstrate the 'listing factors' method. This method is suitable for smaller numbers, which are generally used when introducing GCD in Class 5. It involves listing all the factors of each number and then identifying the largest factor they have in common.
Importance of GCD
Understanding GCD is crucial for:
- Simplifying fractions (e.g., reducing 12/18 to 2/3).
- Solving word problems related to equal distribution or grouping.
- Building a foundation for more advanced mathematical concepts.
