Question

If $50\%\text{of}(x-y)=30\%\text{of}(x+y)$, then what percent of $x$ is y?

• A. $25\%$
• B. $33\frac{1}{3}\%$
• C. $40\%$
• D. $400\%$

Answer 1

The correct option is

D

$25\%$

Given,

$50\%\text{of}(x-y)=30\%\text{of}(x+y)$

$⟹$ $\frac{50}{100}\text{of}(x-y)=\frac{30}{100}\text{of}(x+y)$

$⟹\frac{50}{100}(x-y)=\frac{30}{100}(x+y)$

$⟹5(x-y)=3(x+y)$

$⟹5x-5y=3x+3y$

$⟹2x=8y$

$⟹x=4y$

$⟹y=\frac{1}{4}x$

$⟹y=\frac{1}{4}\times \frac{100}{100}\times x$

$⟹y=\frac{25}{100}\times x$

$⟹y=25\%\times x$

$\therefore y\text{is}25\%\text{of}x.$