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**Question:** If $x$ and $y$ are non-zero real numbers, is $x^y$ an integer? **Statement 1:** $x^2 = 16$ **Statement 2:** $y^2 = 4$ **Options:** * **Choose option A:** If Statement 1 ALONE is sufficient to answer the question. * **Choose option B:** If Statement 2 ALONE is sufficient to answer the question. * **Choose option C:** If Statements 1 & 2 TOGETHER are sufficient but are not sufficient independently. * **Choose option D:** If Each statement is INDEPENDENTLY sufficient. * **Choose option E:** If Statements together are NOT sufficient. Additional data is required.
**Correct Answer: E** **Step 1: Analyze Statement 1 alone** Statement 1 tells us $x^2 = 16$, which means $x$ can be $4$ or $-4$. However, we have no information regarding the value or nature of $y$. If $y=1$, $x^y$ is an integer ($4$ or $-4$). If $y=0.5$, $x^y$ would be $\sqrt{4}=2$ (integer) or $\sqrt{-4}$ (not a real number, though the prompt states $y$ is a real number). If $y=-1$, $x^y$ could be $1/4$ (not an integer). Statement 1 is **not sufficient**. **Step 2: Analyze Statement 2 alone** Statement 2 tells us $y^2 = 4$, which means $y$ can be $2$ or $-2$. We have no information regarding $x$. If $x=2$, then $2^2=4$ (integer) or $2^{-2}=1/4$ (not an integer). Statement 2 is **not sufficient**. **Step 3: Analyze Statements 1 and 2 together** Combining the statements, we have $x \in \{4, -4\}$ and $y \in \{2, -2\}$. Let's test the possible outcomes for $x^y$: 1. $4^2 = 16$ (Integer) 2. $(-4)^2 = 16$ (Integer) 3. $4^{-2} = 1/16$ (Not an integer) 4. $(-4)^{-2} = 1/16$ (Not an integer) Because we still get both "Yes" and "No" answers depending on whether $y$ is positive or negative, the statements together are **not sufficient**. **Logical Trap:** The most common error here is "Sign Oversight." Students often focus on the base ($x$) being a perfect square or an integer and assume that since both $x$ and $y$ have "clean" integer square roots, the result must be an integer. However, in exponentiation, the sign of the exponent ($y$) is the critical factor. A negative exponent transforms an integer base into a fraction, which—unless the base is $1$ or $-1$—will never be an integer. **Conclusion:** Since $y$ can be $-2$, the expression $x^y$ can result in a non-integer fraction. Without knowing the sign of $y$, we cannot definitively answer the question. Therefore, even together, the statements are insufficient.