1. **State the problem:** We want to verify the logical argument: "If a number is even, then it is divisible by 2. The number is not divisible by 2. Therefore, the number is not even." using a truth table.
2. **Identify propositions:** Let $p$ = "The number is even" and $q$ = "The number is divisible by 2".
3. **Logical form:** The statement is $p \to q$. The argument is:
- Premise 1: $p \to q$
- Premise 2: $\neg q$
- Conclusion: $\therefore \neg p$
4. **Truth table setup:** We list all possible truth values for $p$ and $q$, then evaluate $p \to q$, $\neg q$, and $\neg p$.
| $p$ | $q$ | $p \to q$ | $\neg q$ | $\neg p$ |
|-----|-----|-----------|----------|----------|
| T | T | T | F | F |
| T | F | F | T | F |
| F | T | T | F | T |
| F | F | T | T | T |
5. **Check validity:** The argument is valid if whenever $p \to q$ is true and $\neg q$ is true, then $\neg p$ is also true.
6. **Analyze rows where $p \to q$ and $\neg q$ are true:**
- Row 2: $p \to q$ is F, so ignore.
- Row 4: $p \to q$ is T, $\neg q$ is T, and $\neg p$ is T.
7. **Conclusion:** In all cases where the premises are true, the conclusion is true. Therefore, the argument is logically valid.
**Final answer:** The argument "If a number is even, then it is divisible by 2. The number is not divisible by 2. Therefore, the number is not even." is valid by truth table analysis.
Truth Table Validity
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