What will be the Highest Common Factor of 5, 10 and 20?

Options

A. 5
B. 10
C. 1
D. 15

Answer

To find the Highest Common Factor (HCF) of the numbers 5, 10, and 20, we can follow these steps:

### Step 1: List the factors of each number.
- **Factors of 5**: The factors of 5 are 1 and 5.
- **Factors of 10**: The factors of 10 are 1, 2, 5, and 10.
- **Factors of 20**: The factors of 20 are 1, 2, 4, 5, 10, and 20.

### Step 2: Identify the common factors.
Now, we need to find the common factors among the three sets of factors:
- Common factors of 5, 10, and 20: The common factors are 1 and 5.

### Step 3: Determine the highest common factor.
From the common factors identified, we can see that the highest common factor is 5.

### Conclusion:
Thus, the Highest Common Factor (HCF) of 5, 10, and 20 is **5**.

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