Give an example to justify whether:
whole numbers are associative under subtraction?

Answer

To determine whether whole numbers are associative under subtraction, we need to check if the following property holds true:

For any whole numbers \( a \), \( b \), and \( c \):
\[ (a - b) - c = a - (b - c) \]

### Step-by-Step Solution:

1. **Choose Whole Numbers**: Let's choose three whole numbers. For this example, we will use:
- \( a = 9 \)
- \( b = 5 \)
- \( c = 2 \)

2. **Calculate the Left Side**: We first calculate the left side of the equation:
\[ (a - b) - c \]
Substitute the values:
\[ (9 - 5) - 2 \]
Calculate \( 9 - 5 \):
\[ 4 - 2 = 2 \]

3. **Calculate the Right Side**: Now we calculate the right side of the equation:
\[ a - (b - c) \]
Substitute the values:
\[ 9 - (5 - 2) \]
Calculate \( 5 - 2 \):
\[ 9 - 3 = 6 \]

4. **Compare Both Sides**: Now we compare the results from both sides:
- Left Side: \( 2 \)
- Right Side: \( 6 \)

Since \( 2 \neq 6 \), we conclude that:
\[ (a - b) - c \neq a - (b - c) \]

### Conclusion:
Whole numbers are **not associative** under subtraction.

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