Write all the factors of the following numbers :
20

Answer

To find all the factors of the number 20, we will follow these steps:

### Step-by-Step Solution:

1. **Understanding Factors**: A factor of a number is a whole number that can be divided evenly into that number without leaving a remainder. For example, if we divide 20 by a number and the remainder is 0, then that number is a factor of 20.

2. **Start with 1**: The first factor of any number is always 1. So, we can start by writing down 1 as a factor of 20.
- **Factors so far**: 1

3. **Check for Divisibility**: Next, we will check each whole number starting from 1 up to 20 to see if it divides 20 evenly (i.e., without leaving a remainder).
- **Dividing 20 by 2**:
- \(20 ÷ 2 = 10\) (remainder 0)
- **Factors so far**: 1, 2

4. **Continue Checking**:
- **Dividing 20 by 3**:
- \(20 ÷ 3 = 6.67\) (not a whole number, so not a factor)
- **Dividing 20 by 4**:
- \(20 ÷ 4 = 5\) (remainder 0)
- **Factors so far**: 1, 2, 4

5. **Keep Going**:
- **Dividing 20 by 5**:
- \(20 ÷ 5 = 4\) (remainder 0)
- **Factors so far**: 1, 2, 4, 5
- **Dividing 20 by 6**:
- \(20 ÷ 6 = 3.33\) (not a whole number, so not a factor)
- **Dividing 20 by 7**:
- \(20 ÷ 7 = 2.86\) (not a whole number, so not a factor)
- **Dividing 20 by 8**:
- \(20 ÷ 8 = 2.5\) (not a whole number, so not a factor)
- **Dividing 20 by 9**:
- \(20 ÷ 9 = 2.22\) (not a whole number, so not a factor)
- **Dividing 20 by 10**:
- \(20 ÷ 10 = 2\) (remainder 0)
- **Factors so far**: 1, 2, 4, 5, 10

6. **Final Check**:
- **Dividing 20 by 11** to 19**:
- None of these will divide evenly into 20.
- **Dividing 20 by 20**:
- \(20 ÷ 20 = 1\) (remainder 0)
- **Factors so far**: 1, 2, 4, 5, 10, 20

7. **List All Factors**: After checking all numbers from 1 to 20, we find that the complete list of factors of 20 is:
- **Final Factors**: 1, 2, 4, 5, 10, 20

### Answer:
The factors of 20 are: **1, 2, 4, 5, 10, 20**.

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