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Algebra Difficulty 2.0 Junior Find the answer

In the expression xy2xy^2, the values of xx and yy are each decreased 2525 %; the value of the expression is:
(A) decreased 50%\textbf{(A)}\ \text{decreased } 50\%(B) decreased 75%(C) decreased 3764 of its value\textbf{(B)}\ \text{decreased }75\%\\ \textbf{(C)}\ \text{decreased }\frac{37}{64}\text{ of its value}(D) decreased 2764 of its value(E) none of these\textbf{(D)}\ \text{decreased }\frac{27}{64}\text{ of its value}\\ \textbf{(E)}\ \text{none of these}

Multiple choice: answer with the letter of the option you want.

Solution

xy2xy^2
(34x)(34y)2(\frac{3}{4}x)(\frac{3}{4}y)^2
(34)3xy2(\frac{3}{4})^3xy^2
2764xy2\frac{27}{64}xy^2
xy22764xy2=3764xy2    (C)xy^2-\frac{27}{64}xy^2 = \frac{37}{64}xy^2 \implies \textbf{(C)}

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.