Question

If two quantities x and y vary directly with each other, then

• A. $\frac{x}{y}$ remains constant.
• B. $x–y$remains constant.
• C. $x+y$remains constant.
• D. $x\times y$remains constant.

Answer 1

The correct option is A

$\frac{x}{y}$ remains constant.

The explanation for the correct answer.

If two quantities $x$and $y$vary directly from each other, then

$$\begin{gathered} x\propto y \\ \Rightarrow x=ky \end{gathered}$$

$\frac{x}{y}=k$(constant)

Because both$x$ and$y$ increase or decrease in direct proportion in such a way that the ratio of their respective values remains constant.

Hence, option (A) is the correct answer.